Hilgya and (probably) Minrah still off screen.

Keep in mind that Durkon said there are three rings making up the council chambers, each with its own set of... rules? protections? - but Gontor* only seems to know about two of them. The vampires probably don't expect Minrah to show up at all, and may be unclear about Hilgya (or think she could be easily dominated, and therefore not much of a threat).

So showing the Order is like saying, here we are, look at us. Minrah and Hilgya are the good guys' sleigh of hand.