I don't know the ins and outs of US law as i'm from the UK but you definitely have a case of negligence, and breach of contract (your contract will say new vehicle yada yada reasonable delivery use yada yada) the key here is 'reasonable man' test. A reasonable man wouldn't have driven the car like that nor would he expect it to be driven in such a manner (clearly committing all sorts of traffic violations) So you have a right to 'reasonable compensation' You also will definitely win a court case as the law tends to take davids side in a david vs Goliath.
There is also bound to be some violation under agency law by those guys actually committing the offence so i would sue both the dealer, and the individuals. inform bmwna of your decision, and outline your PR activity surrounding this case
and i predict that once they realise you are serious, the dealer will choose to settle under pressure from BMWNA themselves.
