All Bridgett needs to do is point a pistol up the stairs, and plot armour will sort this whole mess out.
I've been on a few vessels before. Some have roomed staircases akin to building fire exits, while others have stairwells that drop directly from room to room. Also, do these stairs have flights? This might or might not directly impact Bridgett's strategy.
I love how Gareth is trying to reason with the guy, and Ben just goes and says that!