I hate to say it, but if you take the risk to loan out your animal and anything happens that's a chance you are taking. IMO those bites are minor considering they could have killed your snake while it was in their care.
I for one would never loan out one of my animals. If someone wants to breed to my animals they can wait and buy a baby from me. I've been asked several times already about breeding loans, and I'm not interested. My sister is about the only person I'll do breeding loans with.