Hmmmm . . . I don't know, Jrabbit. Beth and Jug have indicated that there is some DNA evidence that implicates either Joran or the Kalpoes, and they've never indicated she went back to the room. But who knows? Maybe she did. Can't rule much out at this point.
We can rule out that she went back to the room.
Beth said on Greta's show that N never went back to the room that last night. She seems to be very certain of that. Not sure why though.
Let's remember this young lady was on her way to do her pre-med on full scholarship. She probably let her hair down a bit more than usual for her, but that's all. The rest is on their heads. I think she rebuffed them all. The boys are the only ones who claim they had been kissing.
As for the toothbrush, how do we know she didn't carry it with her at some time during that week? Male DNA on it doesn't necessarily mean the male had been in her room.