I'm just back from GM Goodwrench for an airbag recall. The part in question is as you see in the picture.
It looks like a fresh break, and the repair required pealing the carpet partly back, but I cannot prove that they did this break during this repair. My near certainty only comes from having rarely needed any maintenance on the car, and, aside from another factory recall (about ten years ago, for unsecured side windows), I always went to a mechanic who let me hang around and watch.
I find it particularly nasty that the mechanic at Goodwrench wouldn't tell me that it's broken (I noticed it later). I went back to talk to him because he had left another plug nearby unattached with the carpet loose. If he just handed me the plug and the broken plastic part, I could use some glue and put it back together. I like to treat my car nicely, and, even if it advances in age, would like to keep it intact.
So I'm wondering. Is this sort of thing normal at a mechanic (and the official one no less) and I should just keep my fingers crossed that replacing the airbag ECM and inflator (the subjects of the recall) have actually been completed properly?