Just wondering, why would the freezer be locked with a key?

If this story is true, leave the collection alone. You clearly don't know what you're doing. The reason your brother got you to leave them alone is because he was probably following strict quarantine procedures, which you have just messed up... BIG TIME!

My best advice is to order two cans of Provent-a-Mite from Pro-Products website. Your brother will not "beat your #@$$" as bad if you at least have the PAM on hand when he gets back. Do not use it yourself, its highly toxic to snakes and a specific procedure needs to be followed.