If you just want to change the gender of a male to female, I'd recommend console. Here's an example for a character named Agustin Bean:I can't tell you for sure, but since I have serious trouble getting the game to generate the E-Sports Coach and the Team Leader of the E-Sports Team as anything other than male I ended up trying to find ways to change their gender. From what I read it's not a good idea to use a save editor to fiddle with that & the way to do is through the world seed (which I admittedly haven't understood so far, at least not how to influence the gender of characters) OR one can use the "console" (I assume that refers to the Sugar.Cube stuff) before generating your new world and there is a way to make it so the game will generate only female characters (for e.g. the Football Team, but it should work for Faculty members as well)
Sadly I haven't really gotten to try that out yet, as it seems a bit difficult or at least tedious, so I can't really give you a proper "guide". But here is the post explaining it: https://f95zone.to/threads/course-of-temptation-v0-5-2s-anthaum.190412/post-13965758
V.people["Agustin Bean"].species[1] = "female"
Just replace the name with the name of the targeted character and you're good to go. If you changed the name of one of the characters via character customization you need to use their original name.
The 2 characters you mentioned are special characters that always generate male, so it won't work via world generation unless you fiddle with the code. Some of the story events might not make too much sense with them being female.
To add to that, the masturbation scene can occur on weekend mornings when you wake up and I'm pretty sure I've only gotten the shower scene on weekend morning exclusively as well. You also need to cum in the masturbation scene to progress the event chain.I think those are 2 different things actually. 1 is the Roommate's Partner and the dares, but from what I understand there is something with the roommate, too.
The 1st is relatively easy, to get the dares the player character needs to masturbate when the roommate and their partner are having sex. Not sure if it's once or multiple times (I got the shower scene after the 2nd time) but that is a reliable way to get there. The Roommate's partner will "ambush" the player under the shower in the morning sooner or later, getting back at them for the masturbation thing. It's also the way to change the relationship into a more friendly one (at least stat wise, the game really doesn't handle dominance in combination with friendly very well at the moment).
What seems to be difficult is to get a scene where there's a sock on the doorknob or something when the player returns to their dorm and if they go inside they'll catch the roommate masturbating (from what I understood) and that opens up stuff with the roommate.