Mine has just been in for this, plus rotten wings.
VW contributed 100% to the wing repair but only 50% to the sill repair.
Any things better than nothing right? Seems to vary from dealer to dealer, something that really bugs me 
what did the sill cost you?
VW offered 50% on the wings, but what if i call the VW myself and speak with a warranty guy? what can i tell him to cover 100%?
Actually very difficult to tell you what the exact costs were. I had a few other things done at the same time and the labour charge was just totalled up in to one lot. At a guess and taking into account the other work done i would say the labour cost was around the £200 mark. Pretty much a stab in the dark there though. Dont have the sill covers replaced though as i learned they are super expensive.... Mine have been bonded on now and look pretty neat!
I basically phoned my local dealer who told me to just pop over. He inspected the problem areas for around 15 mins. He was a good guy though as some of the bodywork had been repainted in the past (info which he is supposed to report back to VW) but he '''forgot to write it down''' on the report
Now this shouldnt have swayed it anyway as that was panels that were not near the rust areas. He just said that from experience, they will try and find any way to wriggle out of paying 100%.
Have a bit more of a search on here as there is some info suggesting VW are doing all wings now at 100%.
I can also tell you i had the tailgate handle done which they paid 50% towards.
