So when you hear a pronoun mix like he/they, that's usually shorthand for "I use both he/him/his and they/them/theirs pronouns."
But what does that MEAN? What do you do with it?
cuando escuchas una mezcla de pronombres como he/they, generalmente es una forma abreviada de "Yo uso los pronombres he / him /his y They / them / theirs".
That means you address that person as a he/him/his. You cannot ASSUME they are a girl because they have "he" pronouns, and you can correctly identify them as a male.