[Bryan Herbst]

It's possible that he discussed it with other refs and determined that it was not pinning, or that he thought he entered the penalty in his ref panel but hadn't actually entered it.

In any case, this is the type of incident you want to bring up immediately after the match by standing in the question box. After a few days the refs almost certainly have completely forgotten the incident and all we can provide is speculation, so the chances of finding out what actually happened are pretty slim.