Feeding Mice and Rats human food? Bad? OK?

[Ballpython2]

Ok so here is the question that I have. I have brought home a couple mice and a rat today for my BPs. One wasnt hungry and the other started shed so I need to keep them in a separate tank. My girlfriend started feeding the mice and rat Cheez-Its and Pops Chocolate Peanut Butter cereal. Will that in any way affect my snakes when they ingest the rat and mice? Should I not feed them to my snakes or am I still good to go and they wont get harmed by what they ate?

I was told chocolate is NEVER good for rodents.

but peanut butter is ok because peanutbutter is used to get rodents into mice traps when they are infesting houses and so on.