The closest I remember the Original Quest coming to having red herrings was when Winnowil stated that the Gliders were the 'High Ones' and implied that Blue Mountain was the legendary 'mountain thing.' But even then, as a reader, you kind of knew that wasn't the case. Mostly what I remember Wendy doing is being very good at setting up mysteries and then tying up the lose ends and connecting the dots with a great storytelling flare. She used foreshadowing. She created suspense. But she didn't set you up to expect something that didn't happen, or pull the rug out from under your assumptions. She built up your expectations and then fulfilled them.