Just emailed watchdog probably won't go anywhere but stories like this really pi&% me off! It's a joke!
Keep pushing mate they will cave great tactic written previous with the non serviceable item, its actually visually checked at 120,000 but is still meant to be the life of the engine, they haven't got a leg to stand on.
Also didn't you buy this VW approved?
If so then I would ask why the tensioner was NOT replaced before the car was sold due the fact it is a known fault a revised tensioner should of been installed. I got mine done for a good price in the end and it wasn't even in warranty AND I bought private so keep at them..
Good luck, keep us update!