In the downstairs garage, Neilson takes care unlocking the drivers side door to get into his limousine. In the process he is interrupted by Ferguson at gunpoint. He then takes the bag containing the money and puts in on the passenger seat, through the open window.
When Inspector Hammond returns to his office, the camera is on the inside to see him enter, but the lettering on the glass panel is readable on the inside of the door, whereas it should be in reverse.