Hi mate, I can't see why not as all seem to have the same fitment throughout the model range. Guys like N8 and NHN have fitted the RS6 wheel to A3's and S3's so sure it would go on a Q5. I know a guy locally who has a RS4 steering wheel on his Golf GTi, so they are interchangeable models and other cars in the VAG group.
As I'm selling it as a complete unit, you would have all the parts as I think sometimes there is some extra work to get the wheel alone on if the original wheel is the shield shape and this wheel has the round airbag. But as I have all 3 parts, it should just go straight on.