I wish it was that simple, but that option never appeared on the lot debugger. They weren't even 'off-world', or else they wouldn't be on the phone list.
Am I the only one with this problem? Sims go on dates, dates show up but weren't greeted (either because I didn't know better and stupidly cancelled 'greet' or the action timed out and dropped off automatically from the queue) and then they get 'stuck'?
Edit: I *think* it has something to do with not greeting dates, but I'm not 100% sure of course. I've been trying to find out why some sims were stuck after a date, so after coming back to the base neighbourhood to play, I usually use the 'throw party' option to confirm nobody's invisibly stuck on the lot before a date. I forgot to check while playing earlier, but the teen I mentioned in the first post was the only one in the family to have gone on dates since the family moved in. They've thrown 2 birthday parties for her little brother and I remember being able to invite 20 guests. She didn't go on any dates before that.