For th ose who don't 2ant to feed raw, but do want a high quality kibble, I will point put your shopping mistake.
Do not get "meat" as the first ingredient. You want meat meal, which means that the water content had already been removed. Dog food is baked, so saying "meat" allows them to count in all of that water and move it up on the ingredient list. After cooking, of course, there is going to be much less, sometimes enough to move it to 3rd or 4th on the list. IE a food made with 40 lbs of meat might cook down to 10lbs of meal where a food with 40lbs of meat meal is still going to be 40lbs.
I fed a BARF diet for years. Light on grains, consisting of bone, muscle meat, and organs. I did supplement because I had a lot of trouble finding green tripe. Of course, my dogs got sweet potato and pears as treats, just a slice or two on occassion. All the grain adds is bulk to the diet. A much better source would be green beans or similar. If you buy from the store, always make sure to get "no salt added"
Also, tongue is a muscle meat, not organ. So is heart. Organ is liver or kidney or brain (don't use deer brain if you are in an area with CWD). A good guideline is that most of the diet should be bone such as turkey necks, chicken backs, etc, then muscle meat, and then a small amount of organ. Liver esp is very rich and too much at once will cause the runs.
The reason bone meal is higher in metals than ground bone is water content. By definition, meal has all the water removed, concentrating the material, including any heavy metals. It also means that there is more "bones" in an ounce of meal than an ounce of bone (see above about ingredients in dog food). Ground bones are just that, whole bones broken in little pieces. I never ground bones. Dogs teeth are made for crushing and the chewing means no more dental cleanings! Feed appropiate sized bones - wings for puppies or small dogs, never heavy weight bones like cow legs. Those are fun to gnaw on, but would take a monster dog to actually eat them!