Druydess is that a "Dead Cow" on you horse's head.
Did you find concrete proof that Cordovan leather is exclusively from foals? Also I do believe eating some animal proteins is part of the human make-up as we need vitamin B-12, for our health but cannot get enough naturally without artificial supplementation. Obtaining protien/b-12 from eggs or fish is the way some vegetarians go, as that would be a natural "Human" diet. I believe we are omnivorous beings. I had a Chinese doctor who once said; Humans should not eat any animal protien, from an animal that is larger than themselves. He had good reason for this, and for me it has worked. So eggs, small mammals, birds, seafood.
You could post a video of any slaughterhouse and it would be disturbing to watch, as part of my post secondary agriculture training, we visited some packing houses, it's enough to make you stop eating meat.
As for the First Nations persons being Natural Horsemen, they ate and wore animals so I guess their horses like my horses didn't care, as long as they had a treat in their loin cloths
! The statement Natural Horsemanship is an Oxymoron like Herdbound said, "Does not exist"