That is prudent, but as one of them pointed out, they already passed the paladins...unless they teleported up the stairs in which case we're over our heads as is. Or they both lie really well in which case we kill them as they reveal themselves.
That said, you have several NPCs - since we didn't play with them from level 1, do we know anything about any of them? From the IC thread, I gather that only riftwarden had any direct contact with the party. Viridian is also new in the party and new arrivals now equal in number those of the old group...Keva, Thorn, Banaq (semi-retired), Sir Sheldon (NPC), Mia and Denir (both NPCs) vs Viridian, MetaVoid and deWars new character