controlsdragon

Taravangian did not go see the Nightwatcher until after Galivar's death. From http://www.17thshard.com/forum/topic/7267-words-of-brandon-compiled-x-2/?p=119916 This shows that Taravangian did not make Szeth into Truthless.

You are neglecting two things mentioned in WoK in your initial theory, it is specified that the stone shamans knew of the blade and would retrieve it when Szeth died, and that the Shin want the truthless out of their country as quickly as possible (the farmer in the Interlude had sold Szeth). Szeth was intentionally sent out into the world with an honorblade, obeying anyone who had his oathstone.

The Parshendi do not speak in dawnchant. The Alethi can pronounce it and can recognize it but they have no idea what it means until Navani recognizes one of the things that Dalinar says during one of his visions. And Dawnchant was from the Heralds, who are not Parshendi. This is all towards the end of chapter 60, i would quote it but it is a lot and I have the ebook so I can't provide page numbers.

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