This is outside my area of competence, so take it for what it's worth:

1. When a hotel valet takes a car from a guest, a bailment is created. The duties of a bailee are rather rigid -- among other things, a bailee is liable for all consequential damages, which is to say any reasonably foreseeable damages resulting from failure to safeguard the property of the bailor.

2. The valet is the ostensible agent of the hotel. It doesn't matter whether the hotel employed an independent parking contractor -- the hotel is on the hook for all consequential damages.

In my opinion, a letter from your "friend who happens to be a lawyer" is in order. This is pretty outrageous and you may find yourself rewarded with more than just a few thousand points.