When LBJ's jump shot is falling as it was last night, it wouldn't have mattered if Green was in there or not, imo. I don't think there is one guy who can stop Lebron when he's hitting the J, as it makes him considerably more difficult to defend than he already is. His J hasn't been falling at all during the playoffs, certainly not with any consistency. If he can continue to hit that shot, this series will get even more interesting.
Additionally, he needs to stay in attack mode. Game 4 Friday night was about as passive as I've ever seen Lebron play, and, rightfully so, he was highly criticized for it. James was an enigma Friday night, most notably when Curry & Livingston were on him many times and he chose to drive and then pass it out (after leaving his feet and to nobody who was really that open either) vs. finishing strong to the hoop.