"all that was needed was a bead of SS to stabilize a BB lockring that was the wrong one (and put on by a LBS in Canada - and they were reputable and supposedly knowledgeable). The trip would have ended there IF the frame was Al."

Epoxy should have done it, it would retain the BB without a lockring. Carbon and epoxy or epoxy and wood will repair a lot of aluminum problems. Welding is probably not a roadside option in most places.