Why I don't know. I suppose some people found it "less undesirable" to be called mulatto. Or perhaps the person making the record thought it was more insulting if they did not like the person.
Actually he is not even a “mulatto”.
According to his grandparents and his uncle his real mother was a white and his father was a Mexican stable boy. Even the part about his father being that Emiliano Hilario guy was made up also. He just went to the school his real mother went to and picked a photo out of her year book and declared “well he looks like me, so is my father”, and that guy was Emilino Hilario. Even AFTER his mother’s uncle told him that was dad was the Mexican stable boy, he didn’t want to believe that and made up a story about this other guy, whose ancestor is mulatto to be his father...without any credible ties, just that he thought the guy looked like him.
So even that part his a fake. Boxer created a tribe whose chairman was NOT INDIAN. And now they are going to get a large casino and her son is going to be involved in them getting a casino after she help create their tribe.