I took ownership back in July through Auto Exchange, not ENCS. Here in Italy ENCS only deals with Ford, Chevy, and Dodge. I seriously doubt that our Sirius/XM subscription will be valid once we get back to the states but I think we could make a good argument to them and they may honor it. I don't know where you're at in Germany, but here we have two Audi dealerships that will handle any warranty work and give us the 5K maintenance/check up for free. Your salesman should be able to provide you the info for your area.
Do you have the MMI Navigation system? Have you had it switched out to allow you to use it while in Europe? There is a place in Ramstein that will do it for around 300 euro. I'll get the exact address after the holidays if you're interested.