I found the best way to tame one is to get on a safe cliff high above one, just far enough that a fabricated pistol can hit it (helps to have a scope on it), also have around 50 bullets. Shoot it and it will turn directly straight line to you, as it’s flying straight at you just hold the trigger the gun will fire full auto. If you positioned yourself far enough away the Griffen will turn to flee before it gets to you, meaning you’ve weakened him. At that point switch to tranq gun, chase him and you can force him to get stuck in the side of something, I corralled him into trees and a cliff using my tapajera (any flyer you can ride will work) At that point you just need to shoot him around 10 times in the but with shocking tranq or 15-20 regular tranqs bc he’s weak. Then I just used prime meat. His torpor drains slow so if you need you can even leave to acquire more.