It's "grammaryes".... Dictionary.com spells it with one "m".

But if he weren't going to teach them how to use the key, why were the Sahagin cooperating with Travanchet at all? After all, Travanchet didn't share with the Knights of the Barracuda how to use the key. It was useless in their hands. Unless there was something in it for the Sahagin, I don't see why they would ally themselves with the Ascian.

The Leviathan summoning was already sorta scrapped when the unfortunately real-life events occurred. They WERE going to have Leviathan in the story, but Seal Rock disappeared into the mists again and didn't reappear.