Responses
It's a lot more ambigious in the japanese original, because people don't commonly use gendered pronouns most of the time. I've got the books at home and it doesn't look like the director ever gets referred to in a feminine way or refers to himself as female - after re-reading the last few chapters I actually think the staff knows he's a guy, possibly Shizuma as well (depending on how you read his reaction). I think only Minato and possibly Tatsumi think he's female.
I got really ambiguous vibes from them that entire time, they r female presenting and answer to her so I'll respect that and I urge others too as well but I'd also like to point out how different Minato has been toward them, even when he met the ex so long ago he wasn't this wary of her, at some point in reading I thought to myself 'why hasnt he gotten over this as yet?' 'why's he so wary of this person?' puppy smiles at everyone, this isn't anything new ? Now we know ig.
I just got this feeling that maybe the character was deeper than the surface level nuances we were being fed.