Okay, i havent read threw the whole thread but, at this point their is no reason to call the police. He cant prove they did it and it will just be a big ass hassle for nothing (same thing happened to this dude at a party i was at about a year ago, and the cops didnt do shit) If i were you, i would try to get my parents to pay the 500bux to the insurance agency, and try to salvage out the car and get the money for it (if you have full coverage)
I hope you get some kinda scratch for this shit dude because that is some horrible shit that happened to you.