Your mom has no need to feel guilty. Unless she was with him 24/7, she had no idea of his real needs. That is not her fault. She made the best decisions she could with the information she had.
Please convey my prayers to her. She will overcome her second-guessing.
That’s what I told her, and I’m sure my brother said the same. He looked over the facility with her before Dad moved there and thought it was okay, and Dad was doing alright there last summer.
I think cost-cutting took over, resulting in declining numbers and quality of staff.