An occasional popped rivet is just part of being an Airstreamer. Get a pop rivet gun at any hardware store and a supply of various sized aluminum rivets and get used to it. There are lots of YouTube videos on how to drill out an old failed rivet and install a new one. Look at a couple of those to get the hang of it. If you can, practice on a couple of pieces of junk metal stock.
If you have the same rivet failing over and over again, or if you see a half dozen rivets in one area fail in one towing episode, then you might have an issue to investigate further. Otherwise, don't sweat it.