Yo guys, also happened to me. Two friends of mine helped me to check the gearbox, after an accident (i could not change gears anymore). When opening the gearbox we could not find anything wrong, we tried to shift and it worked. So we plugged erverything together again. My first ride was strange... like a flat tire... I stopped. Brakedisc managed it that the wheel still was on the hub. Two bolts were missing already... and the cap. Well, this was my fault. I did not check if the bolts have been tightened by anyone. Learned my lesson. ;-) Thank god nothing really damaged.
Replaced the bolts and bought a new cap. And always check the torque when mounting a tire with a torque wrench.
But hey, keenerkeen07... you really trust the guys in your shop? I would not do this. If they would have done their job and mouned the bolts with the correct torque the wheel never ever came off.