What I do...
I would go ahead and feed them if they only have one or two spots of freezer burn on them. If they have much more than that, it is up to you.
I can tell you from personal experience that I have fed fuzzys that were about 30% covered with white spots (freezer burned), and they didn't digest (I have done this on two occasions, just to see what would happen). About 2 or 3 days later, the corns pooped a really nasty, brown, hairy thing that looked kind of like a fuzzy and smelled like dead, rotten fish. I know they didn't regurge, because I saw them poop it out!
There was no long term damage from this, the next time, I fed them good fuzzys, and they went back to pooping the same. I just wanted to do this as an experiment to see what happened. So, if more than a couple of white spots, I would say pitch them!
When something is freezer burned, it is drying out from the extreme cold. So, it it’s really dried out, it’s not much of a nutritional meal anymore. To help avoid this, I have now been packaging my mice with my wife’s vacuum sealer (at first she wasn’t to thrilled about this, but I think I have won her over by not spending so much on throwing out old, freezer burned mice).
Brian Miller