Your wife was extremely fortunate.

I HATE going in for new tires, or any place where there is a chance a wheel will be removed. I have even been a victim of lug nut misfortunes when having my vehicles inspected. I always demand they hand torque my lug nuts, and I watch to make sure it is done that way. Don't let them sham you with torque sticks either. They are no better than the person using the air wrench. There is no excuse for screwing up tire/wheel service. This is one example of why I will continue to do my own service work until I can either no longer pick up a wrench, or get back up from the floor.