After all, the best way to test security systems is from the inside. That's why it's called "inside knowledge".
Commentary by memnarch (who has not seen the movie)
What a dusty environment. Holograms are sci-fi tech of some kind of course, but that's just a bunch of dust for the light next to BB. Hm, that would make for a cheap way to keep the detainees from looking out into the rest of the room, or telling how many guards might be around. And while cheap doesn't make a lot of sense for Planet Vegas, this isn't somewhere the people with money would end up if they were keeping their money.
I'm a bit surprised that Rose still has this wrist thingy. Joystick? It kinda looks like a mini joystick when I zoom in on it. No idea what that could be used for. Anyway, if security can lock people up, they can certainly take all of their personal belongings while holding them. At least it seems that Finn and Rose are in separate cells, so the guards aren't completely stupid.
Here's to hoping BB gets a chance to shine and the breakout goes well!
Transcript
GM: Anyway, in the dungeon deep below the casino, some guards are sitting down to play cards.
Guard 1: Deal me in.
BB-8: You said I was thrown on the street. Can I sneak into the dungeon?
GM: You can try Navigation, then Stealth.
BB-8: 16 and 13.
GM: You peer around a corner, unseen. There are three of them. With sidearms and light body armour.
BB-8: Hmm. This is going to take some planning. Where are Finn and Rose?
GM: You don’t know this, but they’re in a detention cell down a corridor.
Poe: Finn! Rose! Where are you?
Rose: We’ve successfully infiltrated Canto Bight. We’re testing their security systems.
Poe: Excellent!
[SFX]: thump! thump! rattle! {Finn bangs the cell bars in frustration}
Finn: Yeah, it’s pretty secure.