Good for you being proactive about preventing water intrusion! I don’t know what Thor uses, but I use clear urethane caulk on my sidewall seems and fixtures. It’s a little harder to use than silicone because it’s pretty sticky but it’s a superior product. I inspect my roof and sidewalls 3 or 4 times a year for smooth, well bonded, unbroken sealant around every single window, fixture and seam. I learned my lesson the hard way. It was a very expensive lesson!