The markups aren't just on the RS6 but also the RSQ8, I've seen one as high as $155k, even used ones with miles are going for high prices (one even at $170k).
The biggest markups I've seen recently is on the G-Wagon. I believe they sold out of the entire 2021 model year and are taking orders for 22's, some at $75k over! As stupid as the ADM's are it seems G-Wagon customers simply want the vehicle, I know someone who is paying $40 over for a G63.