Answer: not vegan.
Quorn is a meat-free product that is mostly made from fungi. All sorts of fungi, really. But sadly, EVERY SINGLE PRODUCT appears to have milk or “rehydrated egg whites.” According to the Quorn US FAQ (as well as the UK FAQ) in regards to being suitable for vegans, “No. Because a small amount of egg white and milk ingredients are used in making Quorn products, they are not appropriate for a vegan diet.”
Not vegan. Bummer. I will continue to pass these by every time I shop. So will you, I assume. That’s ok, I’d prefer a Field Roast product anyway.