Does Medicare and Humana pay on any of my Mom's care?

When it comes to broken bones in that age group, it takes a lot of time to heal, then there is physical therapy.   Back when I broke my shoulder, I had 3 to 4 months of physical therapy 3x a week to get back to normal.   So your Dad could be out of commission for awhile.

Your Mom would probably want to stay in her house, but that would require someone being there 24 hours a day as you already know.   If it is within your parent's budget [it can be expensive], call a professional caregiving agency to have someone come for one shift couple times a week [8 hour shift or less], at least to give everyone a break.

If it becomes too overwhelming to take care of Mom, have her go into Assisted Living until your Dad is back up and about, but that could accelerate her dementia if your Dad isn't there with her.

Once Dad comes home, it would be a good time to talk about Independent Living apartment with assistant living options.   That way he can still feel he is taking care of your Mom, and he will have assistant for himself and for his wife.   Then your folks would be around people of their own age group, make friends, enjoy meals in the common dining room, go to the social hour/activities.   Best to do it while both can still learn their way around the complex.

I am sorry for all your recent problems. Medicare does not pay for a NH or for help in the home. If your father was a war time vet your mother can get help from the VA. It's called aid and attendance. It takes awhile to get this approved but might be worth looking into. Is your mother eligible for hospice? Do you have home health coming in already? Of course both these services are to assist you for short periods of time but they can help. An aid could also come in to help bath your mother. These services are ordered  by your mothers doctor. I'm glad you have siblings to help. This is such a hard time. If your parents have the money for a NH this is the time to use it. If not, it's time to file for Medicaid. The NH can help you with this. Hopefully your dad is able to discuss the finances with you and if you don't already have a DPOA for your dad, it's time to get one. It sounds like it's too late for your mom to sign one for herself. Let us know how it goes. If you'll mention which state your parents live in , you might be able to get more specific answers on what help will be available.   Be very sure not to sign as a responsible person for your parents.