Dementia care for mother?

In the last couple of years my Mother-in-law has been diagnosed with Dementia. She had been living with her daughter for years. Then she moved in with her other daughter. There are 7 kids total-5 girls and 2 boys-they are all over 40yrs old. In the last month she has been shuffled between our house and 2 other children's homes. We have seen her dementia get nothing but worse and quickly. I realize the worse thing you can do to someone with Dementia is what her kids are doing. Her rapid decline is directly related to the unstable living situation. The oldest child has tried to find a way to get her into a home where she would receive more consistent care. Apparently, she doesn't receive Social Security-even though she worked all of her life, has no life insurance, and because of her mother's inheritance of $20,000 in her bank account she has too much money yet still cannot get into a home. Since I am not her child I am have no control over her care or what her kids do period. Is there something they are not aware of that would help her get to where she really needs to be for her own health and well-being while she is still alive?