The extended warrantiy market is a bit of a minefield, although you'd hope an extended VW warranty would be a quality product.
If your extended warranty was bought at the time the car was ordered / built, you've got the Extended Factory Warranty and the level of cover should be the same as the 3 year warranty from date of first registration and it should definitely cover your fuel pump.
If your warranty was bought later, then the extent of cover provided will depend on which of the VW warranties you've got, and the 'small print' might mean you've not got the protection you thought you had, or it gives VW a way out so they don't have to pay!
https://www.volkswagenextendedwarranty.co.uk/Home/Content/Home?name=Home&title=HomeReading the extended warranty info. at the above link;
- depending on what your excess is, you may be contributing up to £250 of the cost of any covered parts.
- the Driveline warranty doesn't cover the high pressure fuel pump (hpfp).
- the Comprehensive and Named Component warranties do cover the hpfp, but for the warranty cover to apply, the part needs to have suffered 'sudden mechanical or electrical failure'.
- if failure is due to normal wear and tear - gradual deterioration caused by the effects of age and/or mileage - then there's no cover.
I'd ask the dealer to explain to you why the part isn't covered under the extended warranty. I bet they'll use the 'wear and tear' argument! I wouldn't have thought it would have worn out yet though.