It sure wouldn't hurt to feed them pre-killed mice as a source of calcium and protein. But my personal view about RFs and their need for protein is that the need is exaggerated. Sure, they eat dead animals in the wild, and they would gobble up every snail and slug that they would find too. However, I often hear of keepers trying to treat RFs like they are snapping turtles or something.
A little extra protein goes a long way I think. Don't overdo it.
From what I have read about your animals everything seems fine.
Oh, here is another good source of occasional calcium that I use.........when we boil eggs to make egg salad I take the boiled eggshells and crush them up really fine and then mix them with other food items. I only use eggshells that have been boiled so that the risk of bacteria transmission (= salmonella) is greatly reduced.