Truthfully, not uncommon. Normal rubbing, bouncing, twisting, you get the point. The fix is as said or somewhat. I've had that happen more than once. Bender, SLP. Where in Co. are you? If cutting out and tig is not feasible, just over plate after cleaning any twisted, warped, bent metal from hole.[ Die grinder, nice.] I've mig'd an over plate more than once. Use material as thin as possible to prevent blow-thru when welding though. Also put buffer metal on pipe below so it does not wear thru. As this will happen. And then very tight springs. But normal movement can not be helped.