Thanks everyone for your suggestions so far, i had a vag specialist take a look today and although he managed to connect to the servers in Germany it would not allow him to remove the component protection. It would appear i need a dealer or similar to send a DISS request/ report direct to the factory so they can approve the equipment for my GTD.
After trying 3 dealers I'm no further forwards, if anyone has any suggestions on how to oversome this please let me know.
As for the kit, I was advised the aerial's are all the same (they're in the rear window) so a different version wasn't needed. Unfortunately as no one (dealer or other) has tried to do this before this is complete speculation until when, and if I can get the component protection removed.