For a good tame, wait till night, set a tame paracer to neutral, the put the little a-hole in a taming pen. Once in the pen put the paracer in the pen and knock it out then stand on it so even if it goes for you it will attack the paracer, you can even speed up the process by hitting the paracer a bit. So good luck
As much as i hate making a tip for this demon, put 3 dino gates down in a triangle and close them all. Put the troodon inside with a flyer or lead it in. Get a parge dinos about rex size. Maybe 2. Put it on neutral. Tranq it. Once tranqed use a tanky dino such as a carbonemys and stand near the rex. Release the troodon and let it attack your turtle while the rex slowly dies. If possible place 2 rexs asleep together to kill both at the same time.