I think that Hoffman & Co usually reckon that the paling-fence-shooter was about 12 ft from the corner, in which case the headshot would have missed Hudson's left earhole by less than 8 ft.
Anyhow, Hudson said that there was no shot from the fence.
Nearly forgot, this here pix shows that there is no shooter behind the fence, or, the shooter was hidden by that tree (in which case he could not have fired the headshot at Z313).
Hmmmm -- i suppose that he could have fired at Z313, if the slug grazed the bark on the lhs of the tree (his lhs, our rhs).
Hoffman put the shooter way down near the west end of the fence. The more common knoll shooter location is 15 ft west of the east end of the fence. Your red arrow on the right is accurate for that. The tree does not get in the way for that knoll position.
The fence is 5ft tall and the branches are only 8 inches above the fence. Only 8 inches of the shooter would be visible. Actually there was a branch hanging down right there so the shooter would be almost completely hidden. That fuzzy photo does not allow us to see if those 8" dark images above the fence and below the branches are people or not.
I think it would be possible for the gunman to step back and retract his rifle in 2 seconds while everyone was still stunned by what they saw. I think almost every single person would have their eyes on the president at the moment of the head shot. So I also don't buy the popular argument of a knoll shooter being too visible.
On the other hand I think the sound would be an issue as Husdon and Mudd should hear it clearer than almost anyone. A shooter 15 ft from the east end would still pass close, about 7 feet from Hoffman, and 9 ft from Mudd. Mudd is the guy on the left in the Moorman photo.
I consider each different part of the knoll shooter theory and let them stand or fall on their own merit. Visiblity, rifle sound, egress, trajectory/wounds, I do not argue any single point as a final conclusion.
Prior to seeing how inconsistent Hudson's recounting of events was I thought his testimony carried some weight. The only possible reasons he would miss a shot from that close is the last two shots being very close together with the TSB shot being first and the knoll shot overlapping and sounding like reverberation from the first shot which he would recognize as coming from the TSB, imo.
In another thread you claimed the knoll smoke seen from by RR guys was actually Oswald's smoke from the 6th floor. You claimed that the knoll position was on higher ground as Oswald was as if the two locations would line up vertically. You provided no math to prove it and it turns out it is very wrong. Ground level at the fence and at the overpass when standing next to the hand rail is within one foot of the fence ground level. Oswald's perch was about 50 feet higher!. The RR guys were looking about level to the top of the fence and Oswald's smoke was nowhere near it. Oswald was also 10 degrees away from the fence laterally. Below is a clip of Holland and Mark lane on the overpass and looking to the fence, go to 1:57. Even if you consider the smoke extended maybe 10 feet out laterally it is very far from Oswald's position. Holland and the others could never have made such a huge mistake.