No. I also doubt she left. Why would she go out late at night?

[Dojima at least does sit down]

It's possible the killer entered our apartment and took her unconscious body away. If they can stay awake despite whatever makes us all be drowsy, then they may also be able to enter other people's apartments.

[...or someone in Apartment #4 is one of the killers, but that's a possibility Dojima wants to keep for himself for now]