Monsters didn't have Unique Racial abilities under normal circumstances. Racial abilities were something only highly intelligent lifeforms could attain.
Even then, the chances of having one were extremely low. Humans, for example, weren't born with Unique Racial abilities. On the other hand, all Lionhearts were born with the innate ability to manifest and control flames.
But the Blood-eyed Minotaur was different. Even if the Blood-eyed Minotaur was on the same level as intelligent races, it shouldn't have been born with a Unique Racial ability!
That was why Michael and the others never thought that the Minotaur might have manifested a Unique Racial ability. At most, they had considered the possibility of the Minotaur going Berserk and thought of a few strategies but that was already it.