I'm so sorry to hear this.
Ordinally I'd question if it was the food or what (because pups can get kidney failure, etc. from toxins). But we already know their vitamin D toxicity issue was causing kidney damage.
BB does have nutritionists on staff and they do have veterinarians on staff (however, they are holistic vets and honestly I would not let a holistic vet touch my dogs). They do not have a veterinary nutritionist. I have to wonder how much experience any of them has beyond just telling an owner to feed xyz kibble or working with nutrient profiles. In other words, I don't believe any have the perfect experience to create a diet that most dogs will do well on.
I think they also skip out on feeding trials, so there was no chance for these things to be caught before marketing the food.
There is just something that I do not trust about this company anymore and my dogs will not be eating it.
Saying that vitamin D overdose has no major side effects, lol, good one. Shows me their vets are top notch.
Or their marketing dept...