Well,,
Where was Aaron Zapruder? Standing on a concrete wing extending out from the steps right next to the grassy knoll. A gun shooting over the fence would have been at his feet level of shot over the fence, and have been about 15 feet to the right. Zapruder was a former army person and he would have seen that person, looking down from above. And he would have heard that shot. The clincher is??? The Zapruder film ends with a look behind the fence and it shows? Nothing there. I say that is not a place where a shot came from. And the people right in front of the fence, within 10 to 15 feet, would have reported that shot if from right behind. They did not.
You’re discounting a few things for n Abraham Zapruder’s film, many of the people near him pointed to the Grassy Knoll, multiple shots rang out in and around buildings echoing the noise confusing many on the location of the shooter and the shooter could have been using a suppressor
Is suggesting a shot from the Grassy Knoll killed JFK any more crazy than suggesting a lone gunman figured out how to get into the school book depository building with a rifle, take multiple shots killing JFK, escaping the building only to be caught in a different location later that day, then another lone gunman sneaks into police hq with a gun and kills Oswald on live TV