Where are you basing this from? This looks nothing like Okiura.

I'd like to know as well because Okiura isn't even credited

Anyways most of this should be Norimoto Tokura (靴がぶつかり転がる真琴) Timing and poses are pretty consistent throughout so prob all actually

looking at the post history it was tagged by an unknown user, and usually in those cases we assume they have insider information since they didn't put the presumed tag

however I agree, it doesn't look at all like Okiura and he rarely goes NC (that we know of)