Wheel centre caps question

[cosmicblue]

Just got my Cab back from Exeter Audi and I've found one of the road wheel centre caps protruding almost falling out.

The cap, its 'tabbed ears' and the round metal ring all look OK - am I right in thinking that the cap is fitted from the inside of the wheel and therefore I need to remove the wheel to fit it?

The dealer had the vehicle back to fix some stuff that it should never left the dealership with (including some shoddily repaired wheels) so they have been off.

Any ideas.....

Thanks