Uthat survived the battle with Kadaena.
Straight from the Nomikos Library ( or the compilated Master Timelines ) :
Utha gathers the few surviving Duskwalkers. They combine their powers to create the Eyes of Utha to guard the planet, and place them in shrines located at the north and south axial poles. That done, they construct a bunker deep beneath the earth and select a few to become a secret order with the intention of maintaining a vigil: if any of the minions of Kadaena have survived, a watch must be kept so that those evil forces can be destroyed. They must ensure the safety of the Eyes of Utha and, secondarily, to continue to close the errant Portals - 'Shadowgates'. These Portals, though severely inhibited by the Eyes of Utha, still allow demonic beings limited access to Kulthea. This cabal is to be led by none other than Utha's son V'gliin - though he would come to be known as simply Daenku. It is made up of eight surviving Duskwalkers and calls itself the Ahrenreth - Ir. "Secret Circle". Relying on sophisticated machines to alert them, the Duskwalkers place themselves in cronagenic hibernation... with the death of Utha - First Master of the Flows - their long vigil begins.
so he died sometime between the death of Kadaena and the time Andraax and the original Ahrenreth went to sleep for the first time