You can waterproof the RGB controller with Hot Glue. Hot Glue is non conductive and works great to waterproof to the IP66 standards.
Those RGB controllers come apart. Solder a wire to the negative and another to the positive solder points on the bottom.
Then trim a corner off the black female power input to get the wires out of the box.
Then cover the inside bottom of the box with hot glue, insert the board back into the box and continue to fill the inside with hot glue. Add some to the inside of the female power input as you will never need this again.
I waterproofed one of the controllers and have in on our dock to provide light around it. I use the 12 volt battery that is used to operate the boat lift.
My plan is to add one of these to my new travel trailer, I'm just stuck trying to figure out where to get power without drilling any holes. I read from the OP something about taking power from the awning? How does that work with the switch inside? Wouldn't the lights only work when you put the awning out?
-Pat