Well, I talked to Siren about it, it turns out that it was there at one time, but she ended up taking that scene out, since it felt a little too "NTR" for her. But if it's any comfort for you, the scene was going to be that same boy coming back to have sex with her. When I found out about the scene being that, it felt kinda anti-climactic. Like, I low-key expected Ann to be having hot sex with one zombie, or even multiple zombies, since there'd be so many in the lab lol
But yeah, the scene doesn't exist, and there's no way to ever get it. So, that case is closed lol