Thanks for all the feedback. I've booked the AAA rate without breakfast. Hopefully they will accept the paper AAA certificate that states that AAA is a partner of ADAC and the AAA benefits should apply.
I shall look into moving some more business from IHG towards Marriott. It won't be easy, though since the Marriott properties tend to be more expensive than what I (or my company) would usually be comfortable with spending.
I'll report back after I've checked in for my 8 night stay.
HTB.