Evidence that there was a subway once.
03_51_01_0004:Check out the subway station on the west side to look for the mystery man.
This texture can be found in game files. It´s probably the subway shop as mentioned above.
What do you think is(was) behind these doors?
Stairway down to the subway was originally in the game as seen here.
Do you think they designed this place only for the cutscene?