Were you able to open it with the Key or Inside (car) release?
The bracket that the actuator pushes against to open will break at some point. The dealer part is the entire mount with the plastic part. From memory it's somewhat expensive. Then there's the guys trying to get rich on 25 cents worth of plastic repair (way over priced). IMO.
I got a piece of welding rod (and good stiff coat hanger should work) and bent it so that it locks into the broken plastic part and ends up in front of the power trunk actuator and mine has worked fine. If you can open your trunk with the key or with the trunk pull, remove the fuzzy cover and see if your plastic arm has cracked or broken off. (Click on the picture and it should open up a larger picture. There's two more on the Tdi site.)