Players are often suspicious of new people they meet. If they're NPCs, that is. Anyone played by the GM is treated as a potential enemy.
But this usually goes out the window if the new character is played by a player. For some reason, a party of PCs will automatically trust a new person if they're a PC.
If only there were some way in real life to tell if the people you meet are fellow PCs or NPCs.
Commentary by memnarch (who has not seen the movie)
Heh, nice of the GM to give Corey an easy win like that. Astromech droids might have a lot of tools for fixing things, but I still don't think he'd have the dexterity to tie the knots needed for that to work. A bolo launcher or those grappling darts could do the trick however, at least as something that gives BB enough time to tase the guards.
And of course Jim takes off running in a random direction. More surprising is that Rose and Finn don't follow. The dude has super lock-picking skills, and you don't want to stick with him? DJ's either got a bad personality that didn't get added in the comic, or Star Wars got an odd dose of realism in this one spot.
Transcript
BB-8: All right, I have a plan. I creep up and tie the guards’ legs together from behind.
GM: Make a Stealth roll.
BB-8: 20! Yes!
GM: As you finish tying their legs up, alarms go off and the guards jump up, then fall flat on their faces. You get a surprise round.
GM: Meanwhile, DJ?
DJ: I exit the cell and go left.
GM: With no idea where that leads to?
DJ: Amor fati.
Finn: Quick, let’s follow him.
Rose: We don’t know this guy. We should go the other way.
GM: This might just be a new speed record in splitting the party after a member joining.
Rey: I started my stopwatch. Would have been sub-60 seconds if Corey hadn’t interrupted.