To tame these guys I prefer to use traps.You can build one easily if you have the items.You can use stone dinosaur gates an large beartraps to trap them.You can find tutorials on the internet.To knock them out you’ll beed a compound bow,a crossbow or a longneck rifle.(I prefer the longneck because of its not so high level engram)use tranq darts with the rifle,tranq arrows with the bows.