To tame one of these just go to the enviroment next to redwood and follow a pretadon in to red wood and watch a thycaleo jump on it then get around 45 darts and a harpoon launcher then when its eating its meal spray it with darts
I got lucky flying through red woods and found a red one on the ground attacking an argy. While it was distracted, I shot it with tranc arrows and knocked it unconscious. I obviously named her Red. BEST TAME EVER!!!