Keep It Simple, Stupid
There's a much lower-tech method of stopping a train, and the risk of you personally getting caught is slight enough to justify sticking around to watch it happen. Just print up some self-adhesive labels with the word FLUSH on them, and discreetly affix one of these next to the emergency handle in every toilet compartment on the train. Sooner or later, one of them will get pulled.
Anyone who has just been is in a temporary state of bliss, operating on autopilot and easily suggestible, so they are much more likely to fall for it. Even if immediately before they began their business, they were thinking Hah! Who the hell were they expecting to fool with a stunt like that?
Wearing the mask, just in case .....
Biting the hand that feeds IT
