Should I bring dad home?

Aloha!
My father is in the later stages of dementia and has been and is unable to make any decisions due to the disease. I have his healthcare and financial POA which the doctor signed off on several years ago.
My father is currently living in A/L with his well-off girlfriend. They had been living together for 13 years before the move into A/L about 2 years ago. The facility she decided to move into is about 10K a month. She made the decision to move without consulting her family, me or my father. My father did not want to move there. He has a life estate in our family home and wanted to move home. When trying to coax him there, at first she said he wouldn't need to pay anything, then she stated that he would only need to pay the difference between him being there and not, which was about $2.5K. He still refused, saying why would I pay when I have a house? My Dad; does NOT spend money. LOL. He wanted her to move there, but because my brother and I live there also, she refused. She begged and begged for him to move with her, and though he never agreed to pay anything, she and I made an agreement to pay the $2.5K a month and he moved there with her after we signed a contract for that amount with the A/L.
My Dad has no capacity to understand payments/rent, etc. My father has a couple hundred grand in savings. My family wants to save these funds for what will eventually be more intensive memory care which none of us can afford. Because there is a 5 year lookback, we cannot get rid of the assets now (He'll be 90 this year) and hope for the State to pay.
Since he moved into A/L, his condition has deteriorated and our family has recently discussed his care. This may just be the disease itself but we are also worried because his girlfriend has her own dementia/parkinsons issues, and has been exhibiting worrying behavior. Very erratic, combative and verbally abusive. When she first moved nearby, I tried to help both of them. Took them to all of their appointments, bank visits, grocery store visits etc. As time progressed, she became more and more abusive and I have decided that I needed to set boundaries and that my primary care was for my father. Her family unfortunately is unable and unwilling to help at all despite my pleas that she needs more care or someone to look after her. We have asked her time and time again not to leave my father alone, and that if she needed someone to take him we would happily come and get him or sit with him. Yet she has continued to do so without telling us. . I have gone by several times and he has no idea where she is. He thinks shes coming back "soon" but when I check the signout log she has signed out for the day. Recently she has asked that Dad pay all of the rent for the unit (10K) which I refused. This month, I went to reconcile his account and saw that she had him write out a check and sign it for the whole $10K. I called the bank to remind them that he is no longer able to sign checks on the account and the account is now flagged. I did let the check go through though as it had already been cashed. I also called the A/L and told them not to accept any more checks signed by my Dad because they aren't any good. I wrote her a letter (to preserve my legal options because she is always threatening me that her son is an attorney) and asked her not to have Dad sign any more checks. I asked her to call me to discuss this and Dad's care and have heard nothing back.
My family and I (my brothers and sister) had a meeting and we all feel he would have better care if we moved him home and brought in home health nurses using his savings.
We are not sure how to proceed? Do I bring him home or hope for the best if he stays there? I just want him to be happy and cared for. She doesn't want to let go and is afraid of being alone and I feel bad about that. But she is in a safe place. The A/L facility also noted his gf's erratic behavior recently. Any advice? Thx!