Its been a few weeks, but I finally have a result!
Went into VW yesterday in Burton on Trent with my V5 to update my details on the system. Gave VW Parkway in Derby a call back this morning (thought ld give them a bit of time for their systems to update). Spoke to Chris Davey who is the guy who originally did the paint measurements and took the pictures for me. VW have authorised the replacement wings, fitted, painted, blended etc... with 100% contribution from themselves. Im made up. I figured that as the car is new to me they would fob me off with "50% blah blah blah 'car hasnt been serviced by VW' blah blah blah 'no customer loyalty' blah blah blah" but l made a point of telling VW UK when l rejected the original 50% offer that my last 3 cars have been Golfs, that l knew about the email mentioned in the original post, this seemed to swing things in my favour.
Car is booked in for 19th May.
If you get a 50% offer I would ring up VW UK, and kick up a fuss. Ive owned my current car for 3 weeks, so the history of ownership, VW service history etc made no difference in my claim, so shouldnt in anyone elses.