Does ORV use wheel bolts or studs? (Studs I would expect.) Press-in studs like in photo below are easy to drive out with a heavy hammer. If not enough stud left protruding out, use a suitable dia. drift. Stubborn studs could possibly need some penetrating oil, heat or a puller. Could also take the hub off and take it to a shop.
I *think* bolts/studs used on travel trailers are usually grade 5. Maybe replace with grade 8 if available?
Yes, odd that it is happening to the same wheel. I'd want to investigate and see if there is a cause instead of just replacing the bolts once more and hoping it won't happen again. Is a wheel bearing loose, does the wheel/hub run true, lug nuts not torqued correctly or maybe bent spindle? Do the shoulders on the nuts have the correct angle to match the rims?