There were a few missed opportunities that I think if he can capitalize on he could possibly have changed the outcome of the fight.
1) Punish TD attempts - A lot of the early TD attempts were nothing more than a ploy to get him to think about the TD's, square up his hips and drop his hands. When Cain is sprawled out on the ground due to a missed TD he just walked away. Take a free shot at his side with a kick, throw a punch, something. Cain got those TD "attempts" completely free.
2) Boxing defense - This is something he actually has always been pretty poor at, just he was good enough to keep everyone at range. He isn't Anderson Silva, he isn't going to matrix dodge punches. He needs to keep his hands up, the more Cain is trying to bring them down the more they need to be up.
3) BJJ - Apparently he is good at it, he needs to know when to try and stand and when to pull guard and go for subs. He completely abandoned this portion of the game and gave Cain free top control.
I'm not saying he would win, but if he did those 3 things he could have at least made Cains job harder. I also didn't list cardio but I don't think it needs to be said.