Due to being in the middle of moving, I missed this occurrence until after it was over. I feel like the situation of serprex and kae sharing the info should not have been penalized and should have been allowed under the current rules. Looking at the rule, it seems like a pretty reasonable assumption to see that the object of the rule is to prevent two teams from sharing information with each other for mutual advantage, or situations like that. When a player outside of any team contributes, some advantage might be gained, but I still don't think that it's especially unfair. When one regularly plays games of any sort with an SO or family member, or even in the same room as, it's pretty normal for some conversation about the games to be exchanged - even if the other person doesn't play the game at all, and it seems unnatural to stifle the conversation altogether unless the two players are actively on different teams from each other.
I wouldn't disagree with removing kae's direct vault access, as vault should probably limited to the official team members, but I have no issue at all with the actual deck helping.
To touch on another issue brought up in this thread, I do think it's fairly clear that tournament deck discussion of all sorts should be actively minimized until after the tournament is over and collaboration should be discouraged. That's a specific tournament rule, because tournaments are in large part competitive explicitly due to the need to prepare for the tournament. If a vet wants to help a newbie, discuss your tournament prep AFTER the tournament is over and walk them through your process. I've done it before and it's definitely helpful.