I was surprised there were very little talk about this on the broadcast, though Kenflo did mention it...Caio hurt Smith, but then put him away with several blatantly illegal shots to the back of the head, including the standing hammerfist that put him down. Followed that up with 3 or 4 more directly to the back of the head.
Is there a chance this would be overturned after the fact?
Wouldn't Brazils athletic commission have to be the ones to overturn it?
If so, no way. 
Unless the initial damaging strike is illegal I can't remember the last time they overturned something. Had Smith survived til the ref got in position he could have called the reset but he was flat already at that point.
If they want fighters to be more careful they have to start calling more fouls. Once people start losing fights that they were winning because of penalties we will see fighters being more careful. The problem is the refs don't want to be the bad guy. They just want to let the fighters fight. Look what happened to steve mazzagatti right or wrong he was trying to doing his job and got punished for making a call.
It should be, but it won't. MMA needs to do something about the inconsistency, in a slow grappling situation, you lose a point, in a high paced scramble you get a win. 
I feel like all a fighter has to say is "oh I didn't know I did that" and it just gets chalked up as a win and forgotten.
If Formiga could headbutt Jorgensen to lead up to a choke, then I think Magalhes can get away with this
Doubt it.
I am getting sick of seeing fouls go unpunished. Start taking points and dqing guys and the shit will stop. But now fighters know they can kick a guy low 2 or 3 times before a point. Eye poke same way. Get a shot to the back of head in the middle of some gnp and no one will notice.
I think it certainly should be overturned, but it probably won't be. Referees need to start enforcing the rules.
Not in Brazil