Make a trap in the redwoods with a ramp for them to go in or forced in. Hatch the egg right next to trap then hurt the baby Dino till it has little to no health then lead into trap. Does not always agro babies so bring a shield and jump in with the baby and camp the baby as the troodon will attack the player with an AOE thus killing the baby Dino.
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.