I count 2 WR's, 1 QB, 1 RB and 1 TE all off the line of scrimmage leaving only 6 players on the line of scrimmage. Illegal formation.
I believe Dan Cambell did not know the rule and thought he could have two eligible receivers. I believe they first reported 68, then reported 70. The Ref knowing the rules believed it was changed fron 68 to 70 causing the confusion.
If the WR on the right was on the line of scrimmage then it is an illegal formation for covering 70.
The refs do not have to explain them the rules.