An explanation.... in part

An individual on twitter.... for what that is worth, stated that Skworonek came in late from the sideline and did not report into the "huddle" inside the hashmarks, prior to the snap. That would be illegal procedure, and I don't know if that is an unsportsmanlike call, but it would explain why I saw the nearside Line judge throw the flag at the snap of the ball. What the offsetting unpsortsmanlike call on the Giants was, I would not have a clue.

I can neither confirm nor deny this conjecture, but kinda makes sense why Skworonek was all alone on the sideline, waving like a Chippie on Friday night on Sunset Boulevard.