If caught most likely no! In reality possession is 9/10 of the law and if they have your car then it is not your car. Taking back the collateral for the loan is all they care about as this is what they get paid to do, take back for the lender the collateral for your loan which in this instance is what was your car.
Yes,he will to get the car back. If you press trespassing charges, they'll probably be dropped when the court learns he was repossessing,