[ViennaK]

The bike has the history of the fault stored in the memory which is more than enough evidence that it exists. Don't take their nonsense response and just share with them how it feels to lose all power going on the center lane at 80 mph and what their responsibility might be in case of an accident. Don't wait too long as the historical error codes are flushed periodically by the ECM. Is the rig still under warranty?

PS: There were several reports of Ks going into limp mode with a variety of root causes from throttle grip actuator to throttle body defects.

 

[ViennaK]

That is about as much as you get from them.
Discuss that with the GM and suggest to elevate the issue to the regional BMW tech rep.

 

[ViennaK]

Go find a different dealer then even if it requires some effort.