BTW we are in a different campground today and I was having a conversation with the guy next to me about the fridge condensation drain tube thing. He bought his trailer new two years ago and after we talked, he called me over because he had apparently never taken the outside vent cover off, so he wanted to see what I was talking about.
He had a condensation drain cup there (Norcold, but similar design) and a condensation drain hose,
but the hose was just hanging there, leaking, hanging outside the cup, and the hose also had a plastic shunt plug in the end of it!!!
It was as if the builders didn't finish the installation by taking the plug out and placing the hose in the cup. There was condensation water dripping out the end of the hose even with the plug in it, and condensation drain water had been leaking on to the wood area there in the vent compartment.
We took the shunt plug out and placed the hose end in the cup. It didn't look like there was any rot from what we could see, but the guy was pretty surprised and said he had no idea it worked like that. I would have not known either if someone else hadn't pointed that out to me and with the help of contributions here.