I wouldn't be too concerned. It was pretty common for that bulk head connector to leak. I think the repair was replacing the internal harness. The vent may spit out some fluid if the transmission was overfilled, but hard to comment without seeing it....
I like the sound of kids having a good time. That is exactly why we do things like camping. To enjoy ourselves. I don't however like the sound of a kid having a meltdown. That's one of the reasons I don't go to Walmart.
I think she may be referring to the booster switch for the tv antenna. I have no idea where it would be either. Does the trailer have a tv antenna on the roof?