Wow, well the first thought that pops into my head is that a thorough check of work he HAS carried out should have spotted that. I mean, obviously opening of the watch case was required to meddle with the insides as part of the repair, the chances that it was all put back together, wound and checked all is well over a period of time and finally packaged up and shipped out to the customer where the screws will have then undone themselves in transit? You are right to be suspicious, I would be fuming.