Forgive me here, as I cannot go back and cross reference to the documents anymore, but there was a variety of cold weather gear found -ear muffs, possibly a motorcycle collar (depending on your reading of shock/snock collar-someone posted a link to an item that matches snock), a ski mask, ??gloves??, a few jackets (?), and maybe more.
Absent from the list, to the best of my recollection, is the freezer itself. If the freezer were a portable chest freezer, I'd think they'd have taken it and not just sampled it.
Is it possible that it is in fact a large walk-in, and the cold weather gear relates to his being in there along with his victim(s)?