The well-dressed guy is striking one of those take-charge poses that railroaders were known for in that era. One popular pose was to stand with legs crossed with the non-weight bearing foot on its tip toe. This guy eschews that pose, but has his hand on his hip which was a standard part of the take charge pose genre. I would say they he is the conductor.
I think that is not the cup handle that he is holding. I believe it is the tender grab iron with the water cup hanging from the bottom end of it.