I agree with you that it was probably just emotion and adrenaline. And, Fedor was probably completely done before those two punches landed. The problem is that because of those two illegal shots, we don't know if Fedor was completely done or not.
How many fights have we seen lately where a fighter lands a perfect hook that clips the back of the head and drops the fighter, practically out cold, simply because of the placement? Because we know that shots to the back of the head can seriously mess with your equilibrium and consciousness, there is a problem when a rocked/dropped fighter is finished with illegal shots to the back of the head.
I agree. At the same time though, it looks like the shot to the back of the head actually woke Fedor up. I've seen that many times before. Flash KO and the next shot or the ground wakes the person up. Kinda hard to tell now. Doesn't really matter what "could have been." It was a good stoppage.