"She seemed human, but fifteen or so feet tall, waif-thin, and unclothed." -Migration 17.1
Also, same chapter: "Her hair whipped around her, nearly as long as she was tall..." so that's wrong.
And finally: "The three largest wings folded around her protectively, far too large in proportion to her body, even with her height." ^these^ seem far too small.
Uhh.. this was actually me agreeing with you (by providing canonical evidence and pointing out other discrepancies), but I suppose I can see how that wasn't very obvious.
Also, taking the position of the shadows, and assuming the red car is some sort of SUV ~6ft tall, that would make her upwards of thirty feet here.