I understand that the Okies are moving around pre-snap, but the defense needs to hold their water and not cross the neutral zone
it was probably a bad call, but not the worst call ever
It was absolutely the wrong call, actually. Definitely one of the worst calls ever, because they got it completely wrong, and it was extremely impactful.
There were 4 things going on there.
1) Multiple olinemen shifting. They are allowed to do this before they are down and before the ball is snapped. However, the rules dictate that this is NOT something that can draw the defense offsides. The only way the defense can be offsides in this case, is if the ball snaps. And if the linemen are shifting when the ball snaps, then it's an illegal procedure on the offense.
2) Two men shifting forward in the backfield toward the LOS. Similar to above, this is allowed before the ball snaps, but by rule it's not something that can draw the defense offsides. The only way the defense can be called offsides here, is if the ball snaps, and if the ball snaps, then once again, that's an illegal procedure on the offense.
3) A covered olineman shifting. Which is exactly what happened. This one is an automatic illegal procedure and should have blown the play dead immediately with an illegal procedure on the offense.
4) Any motions/maneuvers that are designed to simulate the start of the play with the intent to draw the defense offsides unfairly, are also against the rules and an illegal procedure. This play was CLEARLY designed to confuse both the defense, and the refs. I give them credit, it worked, but the refs blew this one badly. 4 different ways it could have and should have been called illegal procedure on the offense, and yet it was incorrectly called against the defense.
And it was obviously VERY highly impactful. Pretty much the worst call I've seen all season long due to the magnitude of its effect on the game as well as the total wrongness of the officials missing it 4 different ways.