firstly I have scuffed the same wheel three times (17" monza II) and had it repaired twice (yes I am a dickhead, but its parking in london, nightmare), anyway it never looks as good as factory finish, but good enough.
secondly your scruff is so small you will forget about it soon enough and you will kick yourself if you scuff the same wheel further down the line.
so personally I would ask for a discount off the service, don't bother with a repair.
re: VW UK, dont bother, bunch of c*nts, dont give a stuff about franchised dealers, they are a law unto them selves.