This shows a chick but just in case you need to make a shoe to get the toes laying normally.https://www.backyardchickens.com/articles/fixing-curled-toes-with-tape-picture-tutorial-and-video.75247/
I don't see niacin mentioned on the label. Since this little one already seems to have a niacin deficiency [it could also be a deformanity] I would go and get Liquid B Complex usually TSC has it Durvet is the brand name of the one they most likely will have it will say injectable but we just...