The Bentley is the factory manual for all Volkswagens and Audis. Period.

You go to a service department at the dealership and look on their shelves, that's what's there. Fact.

Now, if we're talking hypothetical here, and we're to assume that BMW (or Porsche, or whomever) contracted someone else to do their factory-issued workshop manuals and they use some other system than Bentley as the official factory documentation, then yes, you're correct, that would not be adequate in a protest or compliance situation, no more than a cheesy Chilton's would be for a Golf GTi.

But factory is factory; for VWoA, that means Robert Bentley Publications.

GA