Artum, yes there is a extra heavy duty wire. It looks like #10 or 8. There is another like it that was likely the culprit. I have a friend who is an Electrical Engineer and he corroborated all of your advice and concerns. Thank you.
Burl, replace the cord. It's sold at Camper's World and most campgrounds with little stores carry them. As for the screws, tighten all of them. The buss bar is not so much a tube but a bar with tapped holes. I believe most are aluminum and that's the 'rub'. Aluminum wire and other implements have been a problem for the electrical industry. I had a house that was wired with aluminum wire. We had to pigtail off every connection, crimping them to copper leads. Some of the connections, which were NOT subjext to the movement of a motorhome, broke off before I could unscrew them. Just the "movement' from heat expansion was enough to fatigue the metal. So, since our 'houses' bump and jiggle down the road, we have to be more vigilant...something I will be from now on!