the dealershpi is more than likely not going to cover it under warranty. $1500 is around how much the dealership is going to cost you. you can peasily get it under 1000 from a local ship, but its up to him. expensive mistake. You can take it to the dealership and tell them you dunno whats going on with the car, they'll do a compression test on only, they say they will have to take off the head to figure out whats wrong and IF they see that its wasn't driver error then they will do under warranty if not they will charge you.

how bad did he bend his valves?? is he stalling at idle sometimes or has areally low idle. and is there a loud clicking sound too?