Missing bolt on rear suspension on new Class A

I just spoke to my father-in-law. He went up to the Ford dealer and bought the bracket and the bolts. Apparently, the original nuts are welded to the plate on the axle. I guess the welds on the nuts didn't hold and eventually the nuts worked themselves off the bolts. He ended up installing the bracket with some locktight (not sure whether blue or red). I didn't realize this was a known issue but I will be definitely be checking these brackets before each trip going forward.

Burch