I know this doesn't help the OP, and I'm sorry for that, because I really sympathize, but these kind of things seem to happen way to often when letting someone else do the work. This kind of stuff bugs me so much that I have learned to do a lot of work on my cars, over the years, because I just don't trust ANYONE to work on my car and give it the kind of care I want it to be given -- been burned too often.
You just can't trust anybody anymore.
And to OP, if you don't remember hearing a big 'CLUNK' noise as you drove over something you shouldn't have driven over, than you can be reasonably sure it was the dealer who damaged your car and said NOTHING about it.
I'm so expectant of this kind of awesomeness from people these days that I even do a walk around of my car before I leave parking lots, because if someone hit my car with their door, I want to see it immediately so I can ID the car that did it.
I bought my car two months ago, and, on the first day, I had it tinted, and the tinter (I researched and selected the BEST) cut up my rubber window seals and bubbled up a portion of the black paint next to the windows, with his heat gun. Then within a week, someone came out of the adjacent parking spot with enough turn to scrape the front of my car. People don't give a shit. SAD!