+1
go back to them and tell them about this - that is if you fall in line w/ the Magnuson-Moss act clauses. See the Service Manager as well. If no compliance, then go to BMW NA. If still no compliance, then get a lawyer and file a claim against BMW of FFX and have them pay your legal bills, fix your car, and re-instate the warranty.
This is B.S. and is laziness. It is a reflection of technicians who are clueless and chalk up their lack of expertise and naive-ness to do something like this.