Mahomes is a sore loser!!!

Had he checked his positioning with the side ref before the snap like most receivers do, none of this would be an issue. Toney was practically on defense against his own team. If KC would have gotten away with this than Buffalo would have been as livid as Mahomes was. Allen isn’t the star player Patrick is and Mahomes’ frustration is out of not getting a favorable call.
I know the X and Z receivers check with the side judge, often with hand signals, which seems right since they're pretty far from the 5 OL. But, assuming I'm not mistaken in thinking the offsides call was on the Y, can the Y check with the side judge usually? The Y is close enough to the OL that I could see the refs say: Sort yourself out on your own.