They might not have even known there was an accident until later.  A bunch of people are hanging out on train tracks at night.  A train comes, so they (sensibly) decide to go home, only to find out later that one of them was a little slow.  When they were leaving everyone might have just assumed that the absent person was with someone else.  I mean, the alternative would be to assume that someone would just stand on the tracks and watch as the train mowed them down.  Obviously, there are people that… um, "special", but you can see and hear a train coming for miles at night, and there probably wasn't any good reason for the others to think one of their group would be in any danger.

First, what if they guy who was killed was the "new guy", a quiet loner from the "other" side of town.  Didn't come with anyone and no one notices he's missing?   Ok that is a stretch, but ….

Second, I was thinking about it, and I think LearJet is REALLY on to something!!!!!!!  A new show "GHH – Ghost Hunter Hunters"

I can picture it now…Set up some trap camera's around a supposed haunted graveyard… Lead them all into a pit filled with pungi sticks.  Lead them there by setting up hidden speakers giving false EVP's, put flashlights on the ground that turn on by themselves on the path to the pit…   Set up something that will fool KII's so they thing they are coversing with someone.  (In this case they will, but it will be a  live person, not  a dead one).  Have something that is shaped like a ghost give off a heat signature just past the pit (I don't know what, but could probably find something ina  halloween store)…   Lead them until  ::SNAP::   Got 'em!

I'd pay good money to watch that  :-D