Roger that Sir,
As for who might have had this happen on their similar equipped coach, well, that remains to be seen or reported on here. And, the jacks or "levelers" take a pretty fair amount of stress and strain as they begin to lift a coach, ANY coach above the suspension supported weight. Not only are they lifting but, quite often, one or more of those jacks is being subjected to LATERAL stress too. That is, some folks can be off level in TWO directions which means you're trying to level not only front to back but also side to side. And that means those jack mounts are taking stress from multiple directions.
I do have a question for you though. I'm slightly confused here. In your original post, you state:
"...... bracket welded to frame failed." Then, in your answer to my post, you state:
" I did get the bracket off and it rewelded." Sooooo, was the bracket NOT welded to the frame and was/is removable?
Scott