I had a bicycle pedal go down one side of my 1st scheme car, looked pretty bad. Rang RSAM and as was down not down to metal decided it would be left to the end of lease and I got the full gcb, didn’t pay no excess either.
Then on latest car I just give back it had a scratch all the way down the drivers side doors where I think someone keyed it, again it was not down to the metal and also someone reversed into the rear bumper with a tow bar and left a golf ball size indentation right on the edge, again I got my full gcb.
So imo unless it’s down to metal or major damage, ie cracked or broken or big dents it should not be an issue with the body work, regarding the gcb.
However you say the light is broken, this will probally need fixing if any of the bulb is showing or even if it’s just cracked water may get in it and that may cause further issues. One may even get pulled by the police depends how bad it is..