There are plenty of clever ways to get information out of people, without resorting to anything so gauche as threats or torture. Tricking it out of them is so much more satisfying anyway.
You can go full Mission: Impossible and set up a sitation where they believe they're talking to someone they trust. For a real trip, convince them they've died and gone to some sort of afterlife. Just imagine a group of players trying to pull this sort of thing off in a game!
Commentary by memnarch (who has not seen the movie)
Oh wow, those are some faces! Yeah, okay, this has to be a Force Phonecall. No real way to get around expressions like that. I don't think that Luke could have possibly done anything for Rey to get this angry, excepting wildly out of character actions like blowing up the Millennium Falcon or something.
It makes me wonder how this all came across in the movie. Assuming there's no visual info missing, this seems like the kind of scene that would have very confusing transitions rapidly going from Kylo to Rey and back. Or maybe the dialogue is a bit more stilted to allow for a bit smoother of a visual transition. I'm pretty sure the movies doesn't have both halves on-screen at the same time though. It looks like there's been enough of the corridor and the hut shown in the panels to confirm that at least.
And really Pete. Complaining about info being given away just confirms it! You could have made a comment like "Sunlight can be easily simulated. People spend lots of time in spaceships, but there aren't swathes of pale-skinned people running around." Then you've got a proper complaint if the GM shoots that down too. It is pretty funny that Pete did a quick calculation for the search volume reduction though, and that Sally followed up with a question so specific.
Transcript
Kylo Ren: Can I see Rey’s surroundings? Do I recognise where she is?
GM: No, you just see each other.
{beat}
Kylo Ren: How about a nice game of I Spy? You go first.
Rey: Nice try.
Kylo Ren: Twenty Questions?
Rey: I don’t think so.
Kylo Ren: So, Rey... What’s the weather like there?
Rey: What makes you think there’s weather? I could be anywhere in the whole Galaxy.
GM: Kylo can see the sunlight on Rey’s face.
Kylo Ren: Aha!!
Rey: Stop giving away information!
GM: What?
Rey: That narrows it down to within a billion kilometres of a star! You cut the search space down to...
[SFX]: scribble... scribble...
Rey: Less than a trillionth!!
Kylo Ren: What spectral type is the sunlight?