Nope, it certainly won't damage the hoof. His hair might get a little bleached, though.
I would do a few WL soaks over a couple weeks, and make sure that you keep the hoves cleaned daily. And in between the WL soaks, I would put something else into those central sulcuses (sulci?) to keep bacteria/fungus at bay. Pete's Goo (triple antibiotic ointment mixed with athlete's foot cream and put into a small-tip syringe), Thrush Off, No Thrush, Tomorrow cow mastitis medicine, diluted Lysol 4-in-1 Cleanser, and apple cider vinager (I put a little tea tree oil into mine) are all good options that will kill the Bad Stuff without harming healthy hoof tissue.