Hi John-
I do truly hate to dissapoint you, but what you are focusing on in terms of finding a proper food is neither here nor there and does not impact the growth of the puppy. Also your concerns with that particular websites findings should not be at the forefront when choosing a proper large breed puppy food. This website has not been willing to release data to the public on any of their testing or the vadility of it, so until they do, I encourage you to focus on the aspect of nutrition you can control which is finding a food with appropriate calcium/phos ratios and keeping your Ridgebacks lean.
This may possibly mean when your 10 month old reachs 18 months and he is moved to an adult food that your pups are on 2 different foods. Until then, select a food labeled for growth according to the AAFCO statement and one that is labeled for Large Breed Puppies from a company of your choosing.
