You needed to cry foul immediately. If you haven't yet, do it now. The longer you wait, the longer that owner thinks he has gotten away with it. Don't wait until the Sunday games start and it appears you are heading for a loss - since it will make you look like a sore loser. Just call the owner and CALMLY let him know that you were viewing his lineup during the Thursday game, and that you know Woodhead was in his lineup.
I have a friend in my league who prints the "Match Up" page as soon as the early games start on Sunday, even though doing that shouldn't be necessary to prevent a total "dick" move like the one that has been done to you.
I am a commissioner and I had to make a roster change for someone after games had started earlier in the season, and I cannot recall that it showed up anywhere. I might be wrong though.