A) Its about time you wizened up to his scheme
B) Personal property may very well NOT be covered by his policy which is probably minimally insured in the first place. Personal property – computers, furniture, clothes etc. in a rental need to be covered by YOUR renter’s insurance. His insurance would cover structural damage only. And since he hasn’t been legally collecting rent, the apartment is legally vacant, hence there should be no personal belongings for the insurance to even consider covering.
You’re out of luck on this one!!