The questions seem quite open. Usually funds and serious institutions place description of the required fields, or at least underlined examples of what they expect.

You have answered the questions above, although I suggest structuring it and revising it. Have someone within the details of the business look at.
E.g. your platform is currently operating. Not even sure what operating is. It can be operating on your computer at home. It can be deployed on a cloud infrastructure and used by thousands/millions.
Built out is not really a term I would use. What is 'the technology", what part it is from the platform.

Write it in a way, so the person on the other side doesn't ask those questions, and understands where you are.

Further: in the ownership of IP you mention patents. If you really have it, you should also list in in IP protection part.

Number 4 is again a little bit open, but what they mean is an obligation of any kind. Starting from loans, any type of obligating contracts with 3rd parties, employees or others. E.g. a contract that states: I will help you raise this fund, and when you do, you will give me 50%.

Number 5 most likely refers to how do you plan to expand your IP (not only the protected one). Build more features to your software, add more products.

Hope this helps.

Short answer is that you do not, unless you have presence, defined as nexus in the US.
You can read yourself in the many cases you are considered to have nexus from this source: https://www.webretailer.com/lean-commerce/us-sales-tax-ecommerce/
The definition is quite wide and varies between jurisdictions.

If your main business will be in the US, my advice is once you get high US traction, to get a local company in a low tax jurisdiction. Check Stripe Atlas for Delaware companies registration for a start: https://stripe.com/atlas

First you will have local presence and more trust, second you will avoid risking a drastic decision affecting international sales, which we all see can happen really fast these days.

As the business or product is not described, I will answer it for a general SaaS product.
Think from the reseller's point of view. Why will you try to sell it to your community (users/clients/followers). Don't think only about revenue opportunities, but opportunities at all.

1. Commissions, first line of support (any professional task, they can do themselves) - yes, when talking about revenue, if you are thinking of other opportunities, going further should be quite business specific. You already have the general stuff.
2. Value to community - they want to be seen as giving value. So you will need to provide an intensive like a further discount (for the 1st year). Or make a split discount/commission offer, and the reseller can decide on the amounts.
3. Freebies - related to above, you can provide some free stuff, just for their community (e.g. eBooks, free pro advice, tailored to the business).
4. Tailored offers - you can provide offers, tailored to the community of the reseller. Have a landing page, just for them. Tailoring needs to be cost effective, until the channel proves traction! The reseller will be happy to present content, tailored to his community.

I have used in several organizations different solutions. 3cX and Asterisk, but both had problems of different kinds.

Being a CEO, I know professionals in every field of our operations, and I can contact you with very good experts in PBX. I have one in the UK, and another one in Malta.

Drop me a line if you want the referral.

You should evaluate your starting point. Why should anyone give you money to do anything? Do you have a good reputation as an expert in the field? Do you have a demo, mvp, or anything that you already invested in the project? How far on the road with this idea are you. If you just have an idea, you are just starting with it, you have no cash, and you are not a known expert in the field that just wanted to start a business, then there is almost no chance someone to invest, no matter the funding method. So more details behind the story will get you better answers.

I have seen crowdfunding as more common with hardware products, and less common in software. You will need to do a lot more effort for a crowdfunding campaign then to get an angel investor.

My advice is to start by meeting at least several angel investors, take the feedback of what they see as an investment opportunity. If they decline, listen to the feedback and do your homework.

Take into consideration that you have the development team in with some equity, even if it's a slight amount. Perhaps even as a bonus, as it will be better to have them involved in the whole project lifecycle.

The details hide the opportunities.
1. Does the company allow you to issue share options, or shares? Good way is to have an employee share scheme.
2. Do you have a business or product that is interesting for the positions?
3. Does your company associate with strong culture and values?
4. You need to pay them a salary that fits the market. Good to associate good performance with salary increase and bonuses, so they can grow within their performance. This point is the same for all positions.

If going for great salaries is something you cannot afford at the current stage, try to make sure they are paid at least enough so they can cover at least their living costs, be open to how money is spent within the company, so they can see that it is fairly spread. Go for performance incentives (% of profit, etc.), higher future gains (shares/options that will value a lot more in the future). This way you will also be sure that whoever works for you, believes in you or/and in your idea/product/business. And they will invest the difference for a much bigger profit in the future.

Plan in detail for MVP (Minimal Viable Product). When you are bootstrapping and you will be outsourcing the development, it is best to do it in iterations.
When you look for an agency/developer/s see their portfolio, identify previous customers and contact them for feedback.

Best to have it through referrals. I am 15y+ in the industry, and when someone asks me to refer a developer or an agency, I always tell risks, as all people have strong and week sides. I usually prefer not to refer people, unless I am very positive about the outcome, as I will have to put my name to the connection, and follow up the execution.

When you have a contract for the development, make sure you have a long term support clause. Normally it is an % of the base software value paid annually. You should have this at least for 1-2 years for each feature you produce to keep the product stable. So make sure you have this in your budget!

I suggest you talk to a professional, before stepping into long-term relationships. You need to know what you will be producing, how are you going to distribute it. Do you really need an Android/iOS app. E.g. we have a mobile app SaaS business, and after having apps for Android/iOS we decided to go with a PWA app technology, and just dropped the native app support, as it was much faster to install, as our users were coming from our website. But if you rely on the App-Store listings, that's another story, bust still you can do a hybrid app. It is a decision that might increase your costs drastically if you want to pivot once the product is completed.

I advise you to do all technical specifications in detail, including the mock-ups first. Then do the design, then proceed with development.
This can be done either by the agency you hire, or in advance by an advisor/professional in the field, and based on that find the best agency.

Never start development, before it's all figured out in advance!

The product details, which you have not shared here, might be hiding the options you have.
1. If it's something innovative, a commodity that everyone will love, do a crowdfunding campaign.
You have a demo, do your presentation, try to sell it within one campaign. Use the same efforts for the campaign, as you will, when you have the product produced and you will have to sell it (even more effort).
2. Think about step 2, if you have 100k items of whatever it is (no matter how you pay for it), and you have zero cash to market it, how are you going to sell it?

Marketing the product is the thing you should be worrying about. If you have figured it out, the question will already have been answered. But regardless my warning, and if you think you have figured the marketing part out, here are some more tips on the question, besides the standard...getting loans, which I don't advise.

1. Find an angel investor. 15k USD that you are missing is a small amount, that if the product is anywhere good, you will be able to find 1-5 guys that trust in it. Why not an angel club, and get 15 guys on board with 1k. The best option is to have more people with cash, trusting in your idea, even if its 100USD per person.
2. Buy smaller quantities on a higher price, and sell to cover costs. This will validate your idea at a lower cost, you will see the flaws, and will fix it in the next iteration. Then you have your stats, and go back to the previous point with stats. This is always better then getting a loan, as you are just starting and having mentors and experience people involved is more valuable then keeping all equity to yourself.

It's not always a black and white situation. When there is conflict, it is ALWAYS the best way to start with a good casual meeting with the entity involved (bar, restaurant) and loosen up the pressure that normally both sides feel for that many reasons. You should first try to find a beneficial solution for both. You should try to understand what he feels his contribution to the current moment is, and what is the reason he is uninvolved. If he just don't have the time, or other reason, you should together find a solution to compensate both him for the contribution, and possibly you for missed opportunities. As suggested above, you can offer him a buyout valued at his contributiions, or if possible to split assets, and provide him with assets of that size.

You can consider a title "Business Process Manager", unless you feel that the position is really a C-level position, then COO is exactly that.
Have in mind that all positions should be taking pressure off you, and that doesn't make them high-ranked positions.
It also matter of company size (# employees) and structure. If its a big operation, and you don't have a COO, you might as well go with that.
As you will be headhunting for a similar profile in both cases, I would advise you put both on the job ad: Business Process Manager/COO, and decide according to candidates.