And NO, you don't have to replace the whole end cap. You might have a problem getting a regular body shop to quote you though. Most of the ones around here who do four wheelers don't want to mess with any RV.
If it's a dealer you're talking to, he should fix it as part of the deal. If it's a private party, and there aren't any dealer's near by with an RV body repair, consider a boat outfit. They do fiberglass all the time and I used one here in Beaumont, Tx after finding out the only local RV body shop guy had closed down and retired.
And remember BOAT stands for "Break out Another Thousand" and there has to be similar slogan for RV's.
Dan & Linda
FMCA 399045 NKK 22240
2020 Dutch Star 4081 - Spartan K2
2017 Dutch Star 4018 - Sold - Towing Jeep Grand Cherokee Trailhawk