The way I look at it is that it went on there, so it has to come off.

There will be a socket that goes on there and it won't be a special tool that only VW have and that will cost you half a months wages if they are willing to sell it. I have this socket but I don't live in the UK, otherwise I would lend it to you.
Make sure you use a good quality one as cheap inferior ones will split. Halfords proffesional range I think are also guarranteed for life. So if it breaks, chuck it back at them and explain what it is you are doing.