It's obviously Littlefinger responsible for her reappearance. Notice how the poison necklace ended up in the hands of the Grandmeister. That key piece of evidence was last seen with Littlefinger and he'd doubtless have rerouted Shae there as well, without even coercing her to lie.

I don't usually see that as the author's politics, just him describing the motivating attitudes of the characters and their perspective on other characters. Most of his characters are usually experts at something, and that usually comes with a bit of dismissiveness directed towards non-experts in their fields