Uncertain. There are a number of Audi's that have import problems. About 50% are admissible with the modifications to the tether restraint systems and/or the bumper protection systems. Costly in some instances, but could still be quite worth it depending on the model. In the case of the RS6, it doesn't even qualify under the admissible column.
You can see the list of Audi's that can be imported into Canada on page 8 of the RIV's US vehicle admissibility list.
http://www.riv.ca/english/US_vehicle_admissibility.pdf