but even if 68 WAS the one who was reported, STILL a penalty, because he was covered up on the Oline.
No he wasn't. He was the last player on the line on his side.
IF (and we have conflicting stories here) he reported and 70 did not, then the formation was perfectly legal.
The 7 on the line from left to right would be 68 (eligible) LG C RG 70 58? WR (eligible). Then you have the WR at the bottom and the TE on the other side off the ball, and the QB and RB in the backfield.
The refs said 70 reported and not 68. That is what creates an illegal formation.
Whether or not it's the Lions or refs (maybe both?) that screwed up is unknown (though the Lions seemed way more confused about what they were doing - Goff had to tell Decker to go over toward the ref).
We do know 70 was what was officially announced and no effort was made by the Lions to correct that. However, I am not sure how much time was left on the play clock for them to say something. They did not have any timeouts.