I'd like to see pics of both rings on both sides of the mounting holes.
Something has to be different.
Countersunk hole that the chain bolt "sits in" differently from one ring to the other?
Chain bolts backwards or not fully tight. Maybe bolts "popped in" to countersink holes after some usage?
I would expect usage in current state could result in elongating holes over time, depending on how hard & often you use it.
I think defying the law of math makes more sense.