Did they check the studs have not yeilded?
I am not saying they don't know their stuff, and at the risk of insulting them I would say the chances are they don't even know how road wheels are kept on themselves - by that I mean all the stuff about tension of the studs and wheel.
They may have looked and gone, yeah they are straight, the threads look OK but I bet that was it.
There has been some good information given on this forum and I think for your saftey and others around you, you ought to change those studs.