I think this is way off the mark. Fantasy as a genre is entirely predictable, once you know what “the quest” is, the outcome is inevitable. So, its not the achievement of “the quest” but the getting there that really matters in Fantasy writing. With, “The Rain Wild Chronicles”,I found that almost every plot twist could be predicted long before it as actually revealed and thus made reading the books a bit of a chore. There was really nothing subtle about it, the information was blatantly obvious, the “traceable hints” were huge giveaways and I found myself reading large chunks of the book to reach an important “twist” that was revealed forty pages previous.

They get to see Kelsingra but we don’t if there’s no third installment. We are rudely cut off just when the destination is reached.