I had the same problem with running a fan in our bedroom using the t.v. plug in. What I did was buy a 12 volt extension cord - it fits the receptacle and runs the fan very well. I do keep the extension cord bundled so it doesn't fall all over the place. I got the extension cord at Walmart.
Thought you might want to know the result of the call from Jayco. The fella said not to be afraid to force the plug into the receptacle and to turn it. Sometimes something like a fan has only two thingies instead of four or so. I went out, did as he said, and voila, it worked! I told him about your suggestion and he said that would work, too, but the Jayco receptacle is tight. While I'm reporting that all is well, I would recommend the Endless Breeze fan in a NY minute. It really pushes the air (can't think of when I'd need to set it on 3) and only draws 2.8 amps and will come in handy for my pups in the truck and when camping without hookups. I have no affiliation with the makers of this fan--just thought to pass it along to those of you who have dogs or boondock.
Glad you got a good solution. We too could force the plug into the outlet, but when unplugging it, it seemed like it was going to pull the ceiling down with it. That is why I went with the extension cord. Your plug probably has more support behind it. I am really glad you have a good outcome to the problem.
I would like an Endless Breeze, but they are just too costly for us right now. I will add that to our "wanna get" list.
Happy Trails, Okie
TT bumpersticker: "I go where I am towed to" Darling Husband
2 Wonderful Dogs
And Me
2007 Dodge 2500 Quad Cab(Diesel)
2005 Komfort 232TS