The left foot looks pretty good, so you can probably leave the shoe off that one now as long as it's staying that way. I would continue splinting the right foot however. It appears to remain properly positioned while splinted, as much as I can tell from the video, so hopefully with a bit more time it will maintain that when unsplinted. I would continue with the vitamins as well. The B's are very safe. I've attached a picture of some splints that can be purchased (for example). Since the chicks ankle seems to want to roll, if you can devise something similar to this (maybe some cereal box cardboard or similar wrapped in co wrap) it may help keep it positioned better.