Where did this footage come from?

[Jake Maxwell]

In the National Geographic documentary, "The Lost Bullet," there's a several second clip that I've never seen before.
Who took it and when? Is it possible it's part of the missing Zapruder frames....

[Tim Nickerson]

Jake, that's film taken from across the street from Zapruder's position. It was probably film that was done for "The lost Bullet" program.

[Jake Maxwell]

Jake, that's film taken from across the street from Zapruder's position. It was probably film that was done for "The lost Bullet" program.

Tim, What is puzzling to me about it, is that it is has sprocket holes and the same blurry images as a 1963 8mm. I suppose they're able to duplicate that today... though I do wonder why they would have gone to the trouble for bad and barely recognizable 7 seconds...
And yes, Zapruder was on the other side...
What do we know of the missing Zapruder footage?
Thanks...