I have a Russian tortoise but one of her scales was ripped off. Maybe it was her partner that is constantly trying to mount and nip at her. But, now there is a little scale that is red with a scab.
Your little female Russian is lucky that it was only a scale that was bitten off. Male Russian tortoises are VERY aggressive breeders. They've been known to bite off the eyelids of the females to subdue them. Just put a dab of Neosporin (or some such ointment) on the spot and don't worry about it. It will heal ok. Be careful flies don't lay eggs on the spot.