I think the real problem was Cook getting into the ring when he, and people around him, knew he was injured. That wasn't fair to the fans or either fighter. He wasn't faking though - I had the same injury about 4 years ago and it hurts like ****.
I don't think he was faking it for a second but here is the thing: How did he ever pass a medical to fight if he was nursing such a bad back injury? Surely he was looked over at some point.
So if his back felt good then why was he scared shitless of burns punching him around his back area. Look at Cook's face just before burns throws a punch towards his stomoch/back area. He knows that hes injured and doesnt wannt to be hit round there