Neither of the two vids you show of Chiba Sensei are irimi movements.Of course the movements are correct [as one would expect from Chiba Sensei] however neither have direct entry INTO the yokomen attack.Chiba Sensei neutralises both by absorption of Ukes forces.
Back to the drawing board methinks???Cheers, Joe.
Sorry, I was meaning to say the omote version rather than irimi (ura version) because OP was pointing to the "interior entry" which I interpreted as omote. He said they normally do irimi tenkan. The steps I described are for the omote which is why I posted chiba-sensei's vids.