Well, i see a lot of people here talking that they should've have known about it, because it happened in two other matches and forums were talking about this.
But, i think we should start from another part.
The tournament from ground zero should have a rulebook for everyone that is going to play, with every bug that riot knows that exist, but can't solve it in time. All players are supposed to read the rulebook and see if there is something that they normally use that is forbidden at that tournament. In this context, the exploit was not in the rulebook, so its not obvious that they should have known this.
We cant have a list that is incomplete, the players have to read the rulebook and see everything that they cant do. They can't be in the middle of discussing the next tactic if something is allowed or not.
Even if they heard of guild and x10, which i doubt it, as brazilians pros doesn't understand english normally (i know that heat know absolutely nothing of enligsh, at least), they would look into the book and see if the cypher camera was there. If it is not, they can assume that is safe to use.
My question is can we punish some team for something that is outside the rules that they receive?
Discord