Could you arrange to pick him up and have him visit you for a couple of days, when you could arrange for him to go round the retirement villages? Maybe once he saw them, he would be spurred on to sort something out?
Or could you go down to there to this woman’s place with a friend and tell her that she has to tell your father that he can’t live there anymore and then all sit down with him and have her tell him when you’re there (otherwise, she sounds like the sort who would renege on anything you’d agreed)?