Like I said, it depends on the available set of moves. If #1 is +1 and #2 is +0.7, but the cheater wanted to play #5 at -0.5 then that’s an outcome-changing difference.
Chess engines like Hiarcs can show a series of good, ok, questionable and bad moves for each touched piece color-coded on the board for example.
"He was cheating! An outside influence was telling him which move to make and he purposefully didn't do it!"