I think he’s being over cautious, unless the scratch was down to the metal and the dent was major.
Maybe due to many people off the scheme getting pcp contracts which are alot stricter that mb. My last car i handed back just over a month ago had a scratch albeit light, but all the way down the drivers side where someone i think keyed the car you could see white very easily as top blue paint was very thin and it had a small dent in the rear bumper from someones tow bar I got the gcb i was due as i handed the car back early.
On one car i even rang rsa about it and they said is it down to metal i said no and we agreed to leave it till end of lease and got the full gcb on that also.