That's crazy! I had the same thing happen to me about a month ago.
Had my rear brakes replaced by a shop and upon getting it back we noticed a noise coming from them. Took it back the next day and they said it was just fine.
About a month later, while driving to Casper we came to our exit in Casper and the rear end locked up.
Was able to get it to a parking lot and found that they didn't tighten the caliper bolts and the top bolt fell out and the caliper fell into the wheel jamming it up.
They wrote a nice big fat check for me......
Hope it wasn't too fat to fit in your bank account.