This point has already been raised, don't remember to what conclusion.
One thing notewhorty is that the Gods only hear themselves, not the mortals in the Godsmoot, so Dvalin didn't quite hear Gontor's blabbing. That said, all the clerics there heard, and someone must have sent a message to dwarvenlands in order for them to assemble the council of the clans. Didn't they find reasonable to add a "PS: beware of the vampires trying to rig the vote."