This is the version I use:
https://archive.org/details/ZavadaReport
It's the most comprehensive examination of the film possible, made by one of the team leaders of the team that invented the film Zapruder used.
Zavada was considered the world's leading expert on Kodachrome II at the time of the report.
That is a huge, in-depth report! I haven't the time to go through it all but I guess what your point is that the Zapruder film wasn't tampered with, wasn't retouched.
In that case, the differences in the state of Kennedy's cranium between the two frames that I posted proves that there were 2 almost simultaneous bullet impacts to the head.
Unless you have a another explanation?