Computer foul-play Computer Crimes, Hacking

Hi, I am a college student and need advice about an unfortunate incident that took place. I am studying Architecture in Rome for the semester and two days prior to my flight here (a Saturday night. I left Monday morning) the girl I am dating threw me a going away party. I have an Apple computer that I am leasing from my university. For this party, I set up the computer in the living room connected to the stereo to play music with. While the party was going on, someone that I didn’t know was using the computer while I was not in the room. He got bumped into by a girl, and the computer fell off the back of the entertainment center and the VCR fell on the screen breaking it. Through the university, I have the computer insured, but there is a $500 deductable. The girls that live there know the individual that was using the computer at the time, but did not invite him over; he came with some other people. I have talked to him about splitting the cost to repair the computer, to which he refused. My question is, do I legally have a case against either of the individuals, or am I S.O.L.?

Thank you very much for any advice!
Jake