Ironically every generic chain shop I go to charges in excess what my skilled local mechanic does and in some cases more than the dealership. They in most cases are just ripping people off and trying to pay for their shiny store fronts and high end ad budgets.

This is a late model BMW right? Take it to BMW. They cover EVERYTHING short of wiper blades to tires on their warranty INCLUDING service under their warranty program. Just mention your rather astonished that your expensive car with the latest technology would do such a thing and its likely they will explain to you why it happened and fix it out of good will. If not they will likely just charge you a small fee to fix it.