That is a ballsy move if I've ever seen one.
I can see it working... if this wasn't a closed-room conference.
The Onmyou agency is the type of organization that has so many skeletons that trying to open such a closet would be nothing short of a diplomatic nightmare... which obviously any politician is averse to like the plague.
There are people in the room who would very much, from a moral standpoint, not like what they do... but will they take Kyoka's side? That is more complicated.
There are those that seem a little too neutral to the point I don't know what they may think... Ezo kinda falls in that category.
And in last... even if this starts a discussion about the agency, there is no guarantee it will really affect Ren's standing, truth be told... she is too powerful, and it doesn't take a genius to see her ego is too big, it is better to keep her on a "leash", the privileges the position of commander gives her serve too as a deterrent of her going rogue.