It’s a station terminus, not a restaurant. The tracks and platforms are elevated and this station is at the end of the line. You’d enter from street level into a concourse with stairs that led to the tracks above.

The driver was trying to make up for lost time, and the train couldn’t stop in time when it entered the station too fast and the air brakes failed. It ended up smashing through the buffer stops, flying through the concourse and then crashing through the wall onto the street below. Trains have a lot of momentum.