I don't know about the tiggy but I did similar on a Audi a1, purchased the headset and fitted it and straitaway found out that it needed coding after ringing near all the dealers in the country, and I'm not joking?? found one that would code the system for me, but they and no other dealer would code the sat nav part even at the extortionate price of £700 that they charged to code sat navs on A1s
I would suggest that if you want to go down this road ask a dealership beforehand
1 if the job can be done
2 at what cost
Oh and Audi head office just told me to go and exchange the car for one with the sat nav installed :x
Discover uses component protection to prevent systems being stolen and used in other cars. Retrofitting pre-owned units is possible but it's expensive and not permanent either. The Golf we traded in on one of our new Tiguans had Discover Pro and VW didn't even want to try converting it to NZ maps...let alone replace it with a local Pro unit. As far as I could tell it was against VW policy.