Sorry this happened to you. It does seem odd that FR won't warranty such a new RV, but it is hard to tell the extent/source of damage from the pic.
I can see both sides of the story though. Even on an 11 month old auto you have to do maintenance.
I knew my RV had sat on the dealers lot for many months before I bought it. So the first thing I did was maintenance items like the roof, bearings, tires, and wax. And yes, the dicor on the roof seams needed touching up within a few months.
And being in the southwest, roof seams need maintenance at least twice a year.
Get a repair estimate from a service only independent and go from there. Perhaps they could even try to get FR to rethink the warranty aspect.
Good luck and hopefully you can get past this and enjoy your RV.
Scott and Liz - Southern NM
2012 Wildcat Sterling 32RL - w/level up (best option ever)
2007 Chevy 2500HD 4dr short bed Duramax w/allison
Reese Fifth Airborne air ride king pin coupler with Sidewinder