Not sure if anyone has mentioned this, there is a good chance that BG looks shorter and fatter in one ISP image compared to the other ISP image because the image was cropped from different locations within the camera's field of view. Without going through too much technical mumbo jumbo, and not knowing the phone model that Liberty (or Abigail) used to record the video, we can still be sure there is some amount of distortion as an object moves towards the edge of the camera's view.
I mocked up BG on the bridge in CAD, and rendered (1) once with the camera centered on BG and (2) once with BG at the right edge of the field of view. The camera model I assumed in the CAD software was a simple pinhole camera model with a field of view similar to an iPhone turned on it's side.
Below is the result. What do people think? Someone might have already mentioned this, if so, I apologize for being repetitive