Force-tame it, then leave and re-enter the game. The tame will remain, but you won’t be able to open the inventory. If you want to increase its stats, keep pressing the inventory button repeatedly while leveling it up.
DodoRex
The DodoRex is a massive, fast-moving creature combining the body of a feathered Tyrannosaurus with the head of a dodo exclusive to the ARK: Fear Evolved/Ascended event. Known for its immense health and rapid regeneration, it can withstand prolonged assaults, posing a formidable challenge to even the most prepared players. Its unique appearance features dark feathers, a distinctive beak, and small, fierce eyes, giving it an intimidating and otherworldly look.
How ARK players tame and knock out the DodoRex: what to feed it, what to knock it out with, and how to keep it safe.