I think this is up to the tournament organizers to decide what they do regarding these issues yes, not granting the prizes or ban that player from next tournament or just count that game as a loss for him in that tournament are more than enough...
Unless there was a hack suspicion, in which case a SS should have been requested during the game.
Other than that I believe the server where people play has nothing to do with these issues.
From where I stand, banning the player from the game is in my opinion out of the question since the tournaments and its rules are organized and controlled by a tier.
Plus to be fair I think insight is a much better way of getting replays if we could add the chat history to it that would be the ultimate casting tool for streaming/commenting after the game was played.