If he's doing well on the food and likes it... don't worry about protein. If the foods too rich for him, you'll know it on the way out. If he has solid stools, you're good.
It's the amount of calcium that you need to watch out for in these grain free kibbles and large breed puppies. I don't know what the BB wilderness puppy formulas have, but it's something I'd definitely want to know prior to feeding it.