But I would say that Revan was isolated; they tried to reach him, but he didn't respond. Yashur clearly wasn't doing anything, but was there really isolation here?Although, if we assume that, theoretically, Revan could have locked himself in a room and was depressed there, and Yashur was knocking on the door...
I think they both were isolated.
I disagree that Nebo was being watched. They were talking to him and supporting him. Suzanne, based on the description of her role, would rather be creating tension.
But here, only Cliff fits the role.