Do a little research and testing IMO. Ain’t much sticks to silicone unfortunately.
But you’re stuck with it, so….
Have read 3M VHB tape will stick, idk about its UV resistance. Also Sikaflex reportedly, but that seems suspect as I’ve not gotten urethane caulk to work over even residue of silicone caulk. And rtv type sealants may adhere as well. Again not sure about UV with rtv.
Id be thinking, sealant on the threads, dicor or basically anything and maybe neoprene washers on top of the fasteners.
My opinion is I absolutely cringe when I see silicone used as caulking or sealants on RVs and tub and shower applications as it basically makes any resealing a huge challenge. Just say no to silicone!!!lol