I just use whatever 'wax' I use on my vehicles... The decals will peal, fade, whatever, no matter what if exposed to the sun...
Maybe you could clear coat it?? Dunno..
I still have the very first TT I ever bought and that was back in 2002 (brand new too).. The front graphics died awhile ago.. Don't even remember.. I cover it during the winter, but not in the summer (we are using it!)
Anyway, once the front decals went away, I just pulled them off and not really worried about it..
Yes, I know I have a 16 year old TT and you have a brand new one.. Mine was brand new too and I tried to save them with "wax", but it made zero difference in the end...
Yes, I also know that no one keeps their RV's as long as I do and want the most resale value too... I get that.. So, just keep it out of the sun and your decals will do better..
Good luck!
Mitch