I work in the industry, and have had some dealings with VW HQ. I would complain immediately and insist that VW pay for a Hire Car, a Golf, if you have a Golf - seems fair, whilst yours is in the bodyshop. VW own the Daily Rental company Europcar, so it's wooden dollars to them.
I would insist on the following;
Admission of liability in writing.
Commitment to rectify the car to YOUR satisfaction.
A hire car (Golf) whilst yours is in the 'shop.
A letter of apology.
Some form of compansation for your inconvenience.
They are good at customer service at HQ in Milton Keynes, but keep a log of what has happened, who said what and when - get a name from everybody you spoke to and who is involved.
GOOD LUCK!
TC.