We only want my father to go to the nursing home for the 20 days that the insurance pays for and the nursing homes are denying him due to his age and that he is going through cancer treatments they think he will stay longer we want him home he can't walk without assistance and needs rehab to get stronger on his feet
Good luck.
OR is he home and you want him to go to rehab?
Your post does not indicate where your dad is now. If he's in the hospital, the social worker there is supposed to find him a rehab facility that is suitable for him. If you went in and told them you would only allow him to stay 20 days, that may be a different story. They may know from experience that he needs to be there longer and if you take him out and he falls again, they will look bad. There may even be liability issues. You need to talk to the hospital social worker. It sounds like finances are an issue. He may be able to get on "temporary medicaid." If he's not in the hospital, I would recommend taking him there. They will definitely admit him, and then finding him a suitable facility will become their problem. Good luck to you!
If care4pops is doing this on her own and trying to set the terms of stay, it is going to be most difficult to get a facility to take him. If this was all private pay & $$$ not an issue, no problems.
If her plan is for the facilty to get him ambulatory in the 20 day insurance paid window, well a good facility isn't going to ever agree to that. Christine73 summed that up spot-on.
also insurers have issues with a patient signing out AMA; insurer can decline to pay. If dad is not ready at day 21, and they still take him home, insurer may not pay the facility. Facility will have to chase family to pay.
It may be that the family needs to have a reality check on what the 90 day near future is likely for dad (cancer, perhaps advanced elderly, non ambulatory, pain management?) rather than 21 days insurance coverage.