turbo failure is common enough for vw techs to diagnose over the phone. done mine at 150k. had same symptoms you described. in hindsight though i would go for genuine from vw. not from a local garret supplier.
as others here have said, there are other explanations for the symptoms though, so get the codes read.
stuck vanes, theoretically, can be cleaned up. whether its worth it or not is another issue. my bearing was well worn at 150k, meaning it wouldnt have done much more even if i did clean up the vanes.