Al Ghamdi had it easy but was pretty strict, or he had it easy because he was strict. Maybe that first Cameroon goal was not off-side, but the third certainly wasn't and the assistant saw that.
Zambia isn't the team with the stars, but Cameroon is and they were slow, I saw not one player who knew what to do before he gets the ball: they all stop, look around losing seconds.
I think a player who can't even pass right should be sent off, say after ten bad passes. That way Cameroon - Zambia would have ended with 5 against 5 (Zambia without the goalie) and that could have been some match. The Zambian goalie by the way who let the ball slip underneath him for the 1-1. It wasn't even a shot at goal, but - of course - a bad pass.