Dress up as a servent or employee of the train
well in front of nikola's bed is a suitcase in the drawing its closed but once you enter his room its open.
From Eric weises room
lidalida
to get to his room dress up as the porter
In the room with his name on it
In her room and if shes not there she in the room with all the lugage
The luggage room is, a car in the train full of the passengers' luggage. *do not add alternates to this question*
restart the page
you chase him around the train, until you trap him in a water tank
The luggage room (baggage car) is the car between the passenger cars on the train (scond car behind the coal car).
You find a pencil when you enter the train. When you visit Tesla after his arrest, give him the pencil to draw a sketch of the room. Use it to circle the missing briefcase -- you can only do this if you have visited his cabin already.
The luggage room is the "baggage car" between the two VIP passenger cars on the train. There is another "freight" baggage car near the back of the train.