On second thought, which bolt broke? The caliper mount bolts face inward from the wheel and are the most likely to vibrate loose and the caliper slide bolts are threaded at the shoulder/base and also face inward. The caliper itself would drag the inner edge of the wheel and damage it if one of the caliper bolts fell out or if one bracket bolt fell out and the other was loose on many Asian imports I am familiar with. Is there a bolt broken off in the caliper or bracket @AL-curd?
Regardless, though, the shop is most likely responsible for the failure and damage.