Hello.
I even tried a quick trans playthrough and it triggered fine (though there were other issues : inability to talk at the clinic counter on the 8th day; first time encountering the red arrow at the drawer for the extra pill, though I was already at 10 stealth, and it delayed by a day the request for more pills and the launch of the Dream world quest; furthermore, there was nobody to spy either IRL or in the dream world, making that extra pill useless). The only option I've never chosen is the ability to change sex so maybe that's it. Or like you said an old save is preventing it to happen. Sorry for not being that much helpful.
Good continuation.