I would focus on getting the consumer MVP done. Sounds like you already have conducted some interviews for the other two segments. If that is the case, then focus on developing a story highlighting the pain points and benefits for the payers and health system based on the interviews you have conducted so far. You can be upfront with them and let them know that you are still doing customer development especially on those two segments.

Knowing how to prioritize work affects the success of your project, the engagement of your team, and your role as a leader. Even if you have the best project management software on the planet, you are the one who enters information into the tool. And you do not want to fall into the role of crying “top priority” for every other project that comes down the pike. Just as you must be diligent and have the right kind of project insight to ensure that nobody’s working on yesterday’s priorities. Check to see if there are any high-priority dependencies that rely on you finishing up a piece of work now. As a general practice, you want to recognize exactly which types of tasks have top priority over the others. If you have tasks that seem to tie for priority standing, check their estimates, and start on whichever one you think will take the most effort to complete. Know that your priorities will change, and often when you least expect them to.
You can read more here: https://www.liquidplanner.com/blog/how-to-prioritize-work-when-everythings-1/
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath