Anybody every seen a schematic for a Bigfoot?

Have you checked all the wiring between the camper and the truck? My son was diagnosing a blown fuse issue similar to what you are describing. The lights on the trailer and his TC had all worked the week before, but would not work last weekend. After serious searching, the problem was found at the 4-way plug and not his 7-way plug.

Intermittent problems are hard to find. Have someone shake all the wires while you are diagnosing.

Or, you can bypass the fuse and see what melts! :)