I too was one of the people who had their car in the shop for 6 weeks with this issue. The rear camera fault should be stored in the memory, so even if it is not on when you bring it in, your tech should be able to check for fault codes and see it in there.

My dealer opened a PUMA case and the Field Service Engineer in NJ told them to replace the rear camera, which they did and the whole iDrive went down. They had to order a CCC, which took 4 weeks to come in as they are coded by VIN and you can't just get a spare one from another car.

I'm happy to say after a week that my rear camera is working great and they updated my software to 26.2 and I see some changes in the iDrive programming.

-Chris