I'd have a hard time believing that this could have come from BCM like that... but even the best of them put out a lemon every once in a while.
If it were me (aside from taking it apart)... I trust BCM, I'd send it to them for evaluation. If it is a factory defect, I'm sure they'll fix it. They'd probably be able to tell if it was done sloppily by an amateur and caused damage, so then you could take it up with your smith.
And, hopefully this will serve as a lesson. The tools to do this stuff yourself aren't that expensive and you'll know it was done right.

