Since you caught this early, keeping his feet dry and out of any droppings, along with the daily soaks may prevent the need for antibiotics. This is a good article on causes and prevention of footpad dermatitis:
https://www.thepoultrysite.com/articles/what-causes-foot-dermatitis-in-poultry
I would make sure that he is not in wet mud or damp soiled bedding. That looks like foot pad dermatitis. I don’t think I would remove the dark spots, but continue to soak the feet daily.