Hello there and welcome to BYC!!
Yes those are definitely leg scale mites. Soaking the legs in warm Epsom salts, applying Vaseline will over time take care of this. Coat the legs well and rub the Vaseline in well to smoother the mites. This will take months to heal. Don't pick at the scabs and let the fall off naturally. And yes, a round of Penicillin or Amoxicillin will help with any bone infection. No doubt the mites have burrowed into the leg bones and can cause infection and even death
Good luck with her and welcome to our roost!