Did the biner get "nosed" and the top "hinge" got snagged on the steel cable loop?
There was a spectacular Petzl Spirit breakage last season or the year before where the breakpoints were similar as shown in the illustration. The best anyone could guess what happened was the biner got "nosed" on the bolt hanger as the climber climbed above the bolt and proceeded to traverse right. She fell soon after and the "nosed" biner broke. Heck of a ride but no injuries.
Does anyone still flip the top biner "up side down" on draws/slings in situations where there is a chance it could rotate and get "nosed" on the hanger, pin, bong, etc? I almost always get questioned when someone notices I have flipped the top biner.