I was shocked a couple weeks ago when the topic came up and one of my 16-year old sons defended the squatters. He is apparently being taught anti-capitalism in school. Private property is bad, if owner is not living there, it is okay for others to move in since there is a need, etc. UNBELIEVABLE.
Then he should have no problem with you renting out his room and making room for a new tenant.
Rent out his bedroom.