Pathetic BWM Somerset West

I took my X5 for a diagnostic re a Parking Brake caution and both keys not working. They advised me that the park brake actuator and both keys have to be replaced at a cost in excess of R25k. I queried how both key’s batteries can suddenly go flat-even though the spare is not being used. I was again told that that is what happens. I asked them not to do anything. After receiving the car, I reviewed the fuses for the park brake and noticed fuse nr 129 was missing. I bought a new 5Amp fuse, inserted it and the park brake message was gone and both keys worked. I am not sure how BMW conduct a diagnostic, but I would like to believe that with so much electronics, they would check the fuses as well. Then again; compare an hours labour diagnostic bill with a new R2 fuse to fitting a new park brake actuator and 2 new keys in excess of R25k is good money for no work and I would probably drive away with my original parts. I am appalled by their lack of logic after querying the reasoning about the keys. Are they really as compotent as they claim they are or just “new part fitters?”