No not a stupid question mate, quite a sensible one really. In theory you would think VW could do as VW/Audi/Seat and Skoda all use VAS, but I believe that different makes have slightly different coding solutions.
I know you can take your Audi to VW for servicing, belt changes etc as I rang for prices before. But saying that my local Audi (Chingford) will not take in VW cars!!??
Best bet mate, is to phone your local VW dealer and ask.
Let us know, as I am sure a few others here would be interested.