The school had no business permitting that man to live there. It would have been a while other issue if it had been a private home rented by a bunch of students. That’s not the college’s business much less responsibility. That’s when the parent’s power of payment would have to come into play.
It’s not easy to lower the boom on your kid about who lives in shared house if all is going well at school, but I know I’d have pulled the financial plug if aid caught a glimpse of whiff of some of stuff this creep was doing. I did it for a lot less to one kid, and was danged close to doing it to another.