Build a small pen with a foundation a doorway and 2 walls then get him to chase you into the foundation escape through the doorway and place the last wall behind him then add 4 more walls above then a hatch frame at the top then feed him from above
Things not to do when taming one of these guys:
Don't stand while feeding it.
Make sure you're not taming one with a carno in the area (I lost 2 already from wild carnos interfering)
Don't bring any of your dinos with you for backup. Even if they're on passive all it takes is for one of these guys to walk into your dino and start fighting. You may either lose the tame or lose one of your dinos as these guys are very powerful. My level 245 took out 3 guys and 1 of their Pts and their argy. She ended up dying but she died fighting for me. R.I.P Tootsie. Pump up their health and malee damage!
1. Build a taming pen, 1 foundation 4 door frames
2. Get him in there. (Argi works well)
3. Feed him once.
4. Go do some other stuff (Food will drop now)
5. Come back and feed him crouching trough the door frame. He will not agro.
6. Enjoy your new best friend.