Sounds like a real DB dealership, might be a good idea to warn others about them.At this point they are claiming that only a tuner can change the VIN and that the use of a tuner permanently damaged the emissions system as evidenced by the CEL U02A2 - "Lost Communication with Reductant Quality Module". Therefore, the restriction. They won't remove the restriction because of having the wrong VIN on the ECU at the previous visit regardless of if I have the stock ECU at a later visit.
I find it a bit of BS that they say a loss of comm with the Reductant Quality module equates to the emissions system is permanently damaged, comm loss to modules can happen if the vehicle loses battery power when it's disconnected.