@Jason Dalka, just went through this last year. I don't know your market, but seeing your 10-12 property number sounds like a fair bit of overhead unless you're including PM costs to manage it. Taking care of elder dependents can be exhausting and time consuming - don't underestimate it.
Can you find fewer properties that will cashflow the same or better, or were you hoping to have that 10-12 to spread the risk?
Going the private lending route could also work well as suggested above, just be aware of UBIT when sourcing from a retirement account. It's not a deal-breaker, you just don't want to be surprised by UBIT. Related, can she offer seller financing on her current/former primary residence?
Absolutely agree that you or your SO needs to have Durable Power of Attorney to do all of this - mostly b/c it makes it so much easier for you. e.g. If you need to combine all her retirement accounts into one SDIRA, you can set all that up with a POA. Without it, you'll need her signature on everything. It's also time to do a budget review, like phone, internet, newspaper, Medicaire supplement, prescription premiums, and other subscriptions/auto-renew payments that will show up in her bank account. Having POA will make that infinitely easier for you/SO to investigate.
Also, see if you can a copy of her retirement account statements. Find out how much the Financial Advisor has been charging in fees. If the fees are outrageous vs the return, see if they can immediately move it to a non-FA account, which might save a little $ and will buy you time until you figure out what future retirement account custodian to use (if that's your plan, obviously).
Regarding Medicaid, your goal should be to avoid Medicaid at all costs. If you find an elder care facility that accepts Medicaid and if your MIL intends to go there, investigate it thoroughly on-site.