Your valves look a but sorry for themselves.
i was at the dealers today , i asked the master tech why my valves were in such a bad state , he said that oil is picked up in the intake cycle and the turbo pulls a bit of oil through over the intake valves (i would imagine from the intercooler) and this oil mist deposits on the valves.
are vw making a goodwill gesture towards this? how much has it cost you? if you dont mind me asking.