My bootleg way to tame it is to lead a microbe swarm to it then leave the area. depending on the swarms level you'll only need one to tame it, to check the level of the swarm use the button that brings up the hud for using orbital camera and thrird person HLNA will then show you. The best way I've found to bring the swarm to it without trouble is to eat a cactus broth. Once the turtle is tamed it'll show in your tribe log afterwards you just need to go back to its last known location and find it.
DON'T BOTHER DEFENDING THE TURTLE FOR 30 MINUTES!!!! Lure the swarm to it and then just leave render... If no one is near the turtle while the swarm tames it nothing will bother it and it'll tame out on it's own... EzPz
Ps: If ANYONE is in render it won't work, so wait until pop is real low to use said strat.