I myself had a problem with some F/T that I purchased at a pet store. One of them almost looked deformed and the other was half the size as the mice in the package. Although I had thawed out the deformed one I still took it back and demanded a refund. I took the whole package in and got a new one.

I wouldn't feed my children moldy food, I certainly won't feed my snake a funky looking mouse. Hopefully, the place you purchased them will support that idea and give you a refund. Good Luck!!!