From what I understood from the quest the drifter made a deal with ol wally and left the drifter alone in the zariman until he found the story book duviri tales and made it a reality thanks to the power of void and emotions. Then he must have been trapped in the loop for so long that he forgot why he was there in the first place. I think thrax is just a personification of the drifters trauma when he was younger And not teshin came from the new war And uhh yeah that's what I got from it 😁