The Council is going to tread lightly here, IMO. I mean, a hotshot Warden, somebody like Harry who's willing to get the Council into major trouble, could still jump in...
Hmmm....
Okay - here's my take on the "why" of the seventh law. The whys of the other ones are more or less evident, but to ban research on an entire topic - effectively making it a thought crime...
It only makes sense if the White Council believes that when Outer Gates open and the Outer Ones come in means it's game over. Reality as we know ends. Billions die and the survivors envy the dead. That sort of thing. Note that I'm not sure if this is the case but it makes sense that the White Council believes it to be the case.
So breaking the Seventh Law is threatening the existence of reality.
Let's a White Court Vampire gets caught doing something that breaks the Seventh Law. If he's opening a gate the Wardens are likely to kill first and worry about later if later exists (and that's a big if), but it's just something that's a maybe. The Warden who discovers this would probably send word up (using one of those codes that Dresden used in Dead Beat) and the Senior Council would react. The Council... I can see them sending a messenger to the White King saying (in more diplomatic language) "One of your subjects (Tom in Cleveland) is messing with the Outer Gates. WTF? Here we thought you wanted to dominate the world, not destroy it. You want to handle this or is this your way of declaring War on everyone who likes reality as it is?"
And since the White King is firmly against the Outer Ones, he'd handle things... Well, publicly he's against them - privately he probably uses them, or would if his daughter hadn't taken control of him... But Tom got himself caught (or allowed himself to be framed) and now Tom pays the price.
If the Freeholder Lord is up there with the other major players, how will he react when his envoy is accused of threatening reality as we know it? How will the White Council react when they realise that either He sent an envoy to explore knowledge of the Outer Gates OR He lacks control over His own envoy?
Richard