Where in the World is King Hekaton

So, the string of events as presented in the book:

King Hekaton believed that his daughters, Mirran and Nym weren't fit to rule, so he told his wife Queen Neri that he wished to appoint his daughter Serissa as heir to the throne. Neri warned him against declaring any such pronouncement, but he did so.

Mirran and Nym stewed in their anger until this newcomer Iymrith came in and stirred them to action.

Iymrith petitioned the Kraken Society, who agreed to kill Neri and kidnap Hekaton. Iymrith let them believe they were coming up with all the ideas, while offering to "do the legwork" for Neri's actual death. So the cult kills her and makes it look like it was done by one of the factions she went to go visit. Imperator Uthor finds her body and the planted evidence, and returns to Hekaton with the obvious conclusion.

Then, Mirran and Nym feed Hekaton false information about rumors they've heard of who was behind the killing, and where he could find them. He, in a rage, left to find and kill the assassins who killed his wife. When he got to the location indicated by his daughters, he was ambushed by the cult and imprisoned in Morkoth, where he sits today.