Retains its original name after taming. Chimaeron can only be tamed when he's under 20% health. If you're high level you'll have to be careful you don't kill him. If necessary, remove all your equipment. You can also kill yourself outside the instance and take resurrection sickness to weaken yourself further.
Level scaling: In Shadowlands most NPCs will scale with the Hunter's level, within the constraints of their level range. Hunters can tame regular NPCs up to 2 levels higher than them, but can only tame elite NPCs of the hunter's level or below.