alert!
What an insightful response to the evidence and arguments presented, demonstrating the film evidence of the head wound in the Z-film verifies the autopsy photos posted and vice versa.
A really inspiring response from someone who clearly wants to learn what actually happened that day and who is happy to consider evidence that might inform their opinion regarding the assassination of JFK.
A lesson to us all.
Further evidence the top of JFK's head was blown off is found in the Z-film.
At the moment of impact two powerful "jets" of, what I assume are skull and brain tissue can be clearly seen in the film. The main "jet" is picked out by the red arrow, the lesser "jet" by the yellow arrow:

In the frame below, the yellow line represents the line running through the top of his head. This is my own rough estimation and is made to give a general idea of the direction of the "Jets" (marked in red). There can be little doubt these powerful "jets" of skull/brain material are travelling in a straight line from the top of JFK's head. There is nothing even remotely similar exiting the back of his head.

The small fraction of one second this frame represents gives an idea of the speed and power of these "jets" exiting the top of JFK's head.
There is a weird moment in the video posted in the OP of the Jenkins interview (around thirty minute mark). At one point Jenkins describes the injury he sees to the skull:
With a model skull in his hand he places the position of the injury towards the back of the skull, right next to the occipital bone:
"The wound was here, approximately where my finger is [he places his finger on the back right of the skull, next to the occipital bone]...and it extended down here. It was about three and a half inches long...about two inches wide. That was where the missing bone was and the missing tissue was."Here he is describing the classic "blow-out" injury to the back of the skull. A defined hole at the back of the skull. However, he then goes on to say:
"Remember, all of this portion [of the skull] in this area was fractured to the saggital suture[he indicates nearly the whole right side/top of the skull]...but it wasn't gone, it was still being kept intact by the scalp. The scalp had rents and tears in it [he indicates a line running along the saggital suture on the crown of the skull]...it seemed like some of those tears in the scalp had been surgically connected, little connections to follow the fracture line in here [again he indicates the length of the saggital suture on the crown of the skull]...
When Dr. Humes took the wrappings off the head, there was a secondary wrapping on it that I think was a towel...as he was taking it off this area kind of gapped open [he indicates that the whole top right side of the skull from the saggital suture downwards opened up] but as soon as we separated it from the towel it went back together."Here, he is clearly describing the injury we can see occur in the Z-film. At the moment of impact the majority of the top right side of JFK
s scalp is blown to the side and is seen as a large mass of red flesh hanging by the side of his head. This is the exposed inside of JFK's scalp. It is also the injury seen in the autopsy Gif posted by John.
Jenkins goes on to confirm this:
"Now, that's significant for the fact is you could actually...lay this skull open, you could actually take your hands and separate it [he makes a motion with his hand to indicate the side of the skull could be opened up like a small, hinged door]. So, that would have given you access to the brain."There can be no doubt that Jenkins is describing a massive wound to the whole top right side of JFK's skull and not just the defined area of the "blow-out" hole. What is weird is that he doesn't relate this massive injury to the headshot, he seems to believe that this was a procedure that was carried out before JFK's body reached Bethesda.
The Z-film shows he is wrong to believe this and that the large "hinged flap" of scalp/fractured skull was a direct result of the headshot.
So, Jenkins
does see the massive skull wound that we see in the autopsy Gif but he doesn't recognise it for what it is.