Vex's declaration was met with multiple reactions.
The first one was that of the crowd. Numerous heads started turning around in a desperate manner to lay their eyes on Black Fang while shouting exclamations of pure shock. While Veil Walkers were already rare to see, Obsidian Circle Members were living in the shadows completely. That didn't mean that none of them had at least some information available about them, after all, they were all Phenoms once but not all of them were as secretive as me.
For example, I'd learned that Orianna was one of the strongest Veil Walkers and thus had a good chance at succeeding one of the heads should they become 'unavailable', at which point her identity would not become immediately forgotten.