FWIW: its more than just a single mechanic failure as there is a QA system that failed also. So it will be interesting to see if the forthcoming SB will explain what happened.
That said, all rings/clips have a sharp side and a round side. However, some have an additional 10 deg bevel on the round side and fall under different specifications and part numbers. The beveled rings need a corresponding beveled/chamfered groove to be installed hence the specific direction. In general, non-beveled rings/clips have no specific install orientation as the grooves are uniform. But all are still considered standard parts.
Regardless, if the ring was beveled and installed backwards then it would have also failed the minimum ear gap check of .179 “ as well. So not one but 2 failures in the system. And with 50+ years of no ring/clip failures its not a design issue but unfortunately a human issue.
FYI: the SB 99-3 I linked above has zero to do with this issue. The SB corrected a bushing install problem not a ring problem which was causing cracks in the crank. I used it strictly because it had pics of the same area.