Wouldn't this mean the mk7.5 CSS muffler should fit then? It has bigger tips which is a plus for some.
The eBay auction has ended so I'm not sure this link will work. Check the description. Maybe I'm misreading it.
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/322947624161
There is no 7.5 CSS or CS. The tips on 7.5 GTI is bigger then the 7.