Traitors NZ question... Season 1. Different rules about murdering?

We're watching season 1,and just finished episode 8. Are the rules in NZ different somehow?

At the end of the previous episode, the traitors tried to kill Anna, but she had a shield, so no murder occurred. At breakfast the next morning, no one discussed the ramifications of no murder occurring. Specially, this meant Anna was 100% faithful. If she was a traitor, she would have murdered someone since no one else had a shield. Since no one died, that means someone ELSE was a traitor. Right? Am I missing something? It also means Julia is almost certainly NOT a traitor, since she knew who had the shield. Yes, she could have purposely targeted Anna to make her look even more innocent, but this late in the game, you have to eliminate people when you have the chance, so she certainly wouldn't waste the chance. Why wasn't any of this discussed amongst the players?