There are three different people you can talk to to continue this quest.
The right person to talk to is the one behind the "Railroad" (or whatever that might be)
You have to ask the questions in the correct order. (i dont know exactly but i think it was 2,1,2,2)
Just test it out
Mann muss mit der Bahn (Railroad) fahren und dann mit Regulator Milla reden (Nach der Bahn gleich links).
Die fragen müssen in dieser Reihenfolge beantwortet werden (2, 1, 2, 2)