How can Mom keep her HUD apt without jeopardizing Medicare?
This is an excellent question and one that may require a lot of action on your part in the next few days to find a resolution. If I were you here's what I would do:
1) Consider what the most realistic outcome is here - in other words, based on your mother's age, the kinds of surgeries she's had, and her physical response to the rehab thus far do you think that she will ever be able to manage at home on her own or with minimal support again? If you aren't sure, contact her primary care doctor, share her most recent history and ask for some honest feedback. The answer is critical. If you determine that her return home is probable if she can just hang onto the apartment, then it is obviously worth fighting for. Otherwise it's not.
2) Assuming that your mom is expected to improve and could return home after additional rehab, there are a few things to consider. First, what is the intensity of the rehab she's currently receiving and could it be provided at home? Perhaps home physical therapy was not an option for your mom upon hospital discharge because her skilled needs were too great, but what about now? What is the rehab facility doing for her?
If you have knowledge of the daily routine and it seems as though they are merely housing her there and providing a minimal amount of therapy per day (i.e. no other skilled needs are being attended to - wound care, i.v antibiotics, etc.) then it is worth exploring having Medicare pay for home physical therapy. This would mean that you would be asking to have her discharged from the rehab to save her housing and then having the facility write orders for home physical therapy.
If the facility were unhelpful with this process you could also ask her primary care doctor to do it. Regardless, it's important to know that Medicare does pay for home physical (and occupational) therapy. Of course nursing homes don't broadcast this info or go out of their way to assist you in getting it because they get nice payments for having your mother do "rehab" with them. :)
3) Contact the HUD office and find out how the building records an "overnight" visit. I'm sure you've thought about this but I'm wondering if bringing her home early in the morning and having her stay there for a long day (maybe returning her to the nursing home at 10pm) would be enough. To be clear, I'm definitely not suggesting fraud here, but I would be curious about how long of a stay is long enough for HUD.
Hopefully the above suggestions have provided enough info to get you going. Just one more thing to add: if you can physically get your mom home for a night and take care of her on your own without killing yourself, that says a lot to me about her current functioning. What it says specifically is that she may not need the rehab any longer. If that's the case, I would advise you to fight hard to keep her apartment. The alternative will ultimately be a permanent stay in the facility she's currently in or some other facility, but not home.