We should let the judges in on Teamspeak to prevent ghosting, at least for the finals.
I'd support this if we had any unaffiliated arbiters, ie. arbiters who are not in or close to any clan. The organisation in TeamSpeak during an important match tells a lot about a clan and can be used in future matches. The clans would need to trust the referee not to pass on any information. Without any criteria for arbiters, I don't see that happening.
If there aren't any spectators, nobody can ghost. So having no spectators seems like a better solution, in my eyes. That would of course be problematic for a live astream, but if that stream could be delayed even longer then 10-20 seconds, I think both sides of the argument can be satisfied (viewers can watch the game freely, the teams don't have to fear for ghosting or admins that might inform others about their Teamspeak-organisation).