Out of desperation I bought a gallon of white flex seal. Yup the "I cut this boat in half" stuff.
i can not believe how awesome the liquid stuff is. It is really thick pouring and I used a 1/4" nap roller to smooth out the non-leak areas. If you pour it thick it cures thick so it works really good around the horns and antennas etc.
The best part of it is it dries flexible but really tough and super glossy. The part of the roof I put it on is super reflective. With it being so glossy it should take a while before dirt sticks.
I have a 38' manaco and I need to buy another 3-4 gallons more to do the rest of the roof. But I want to wait a bit to see how it holds up. I will say it is far better than the cool roof and elastomer stuff I have used in the past on other rv's.