I had the same problem. After founding the totem of Tikti I went on another quest. And to the others who replayed - it's not possible to reach the totem of Yor because without the "power of serpent" or whatever I am too unable to swim underwater, which makes reaching the totem imposible. I also tryed to retake the mission but again I swim on top of the totem... So... I'm stuck aswell!!!!!!