Given the size of the coop and the circumstances, separating them from the flock and not reintroducing them at all is the best option in my opinion.Chickens recover from wounds like that remarkably well. Some of the suggested treatments sound like people are unnecessarily going overboard on treatment. I did too when I first got chicks. I suspect most of the time no treatment is necessary for skin wounds at all, but I do usually do one smear of antibiotic ointment. Separating them from the rest of the flock and not reintroducing them until they are adults is however good advice.