I'm surprised neither Verin nor Sheriam was named as Supreme Council given the hints in the books.
What hints? Sheriam was an inept loser, and Verin was trying to lie low. On the Supreme Council, she'd have to actively work for the advancement of the Black Ajah and help set the agenda. Verin's entire M.O. is to make people overlook her and underestimate her. She'd have followed enough orders to not get in trouble, but no more than that.
If you mean Sheriam's comment regarding the revelation of Verin as the source condemning her, that was so ineptly written and out of character, it can't be taken seriously.
The fact that Sheriam was aware of Verin as BA for one. Also the fact that Egwene said something to the effect of "Verin's book said you sat high amongst them" when she busted Sheriam. The fact that both Aran'gar and Mesaana (who we are told sought out the council) went to Sheriam rather than another woman who might have been on the Supreme Council.
Verin was indeed lying low ... Verin needed a degree of freedom to be able to hunt members of the Ajah without being easily caught out. But she is far less likely to be on the SC than Sheriam appeared to be.
