There are only a few named characters in the story but there are other insignificant inhabitants of this strange land that go through the book nameless - such as this “unsuspecting victim”, an ill-omened pawn dubbed a “cookie cutter.” Pray, what of this profession of cookie cutting?
"As I remember, John gave me a copy of Pedant without comment and I don't know why he called the character the ‘Cookie Cutter.’ To me, a cookie cutter is a baker, and that's the way I pictured this person.”
Maybe Bellairs used the term to describe this “unsuspecting victim” as boring, mediocre, or easily persuaded (i.e. another “cookie-cutter” victim?).