> That’s pretty interesting because from a “theory of film” point of view, the added text, or even the script, does it have the same weight of truth as the actual shots?

It has more weight than the actual shots. They used a real building to depict a fictional location. Due to an editing oversight, the real building's name appears in one shot. The fictional character in the fictional story was held in the fictional location, as indicated by the script and the supertext.