It makes no sense that he would have used it for his first, very near, shot.
But maybe he did, and maybe his doing so -- in conjunction with his standing and awkwardly leaning forward while firing the steeply-downward-angled shot -- caused him to miss everything.
LHO most likely purchased the scope for use at the Walker residence in April ‘63. That shot was approximately 100-feet. According to my calculations the distance of a first shot at ~Z133 was about 104’. A shot at about “Z124” would have been only a very slightly bit shorter, maybe about 100’. For what it’s worth, I use a scope for shooting airguns in my basement shooting range. It is only 10-meters (33-feet). This setup and scope usage is very common among airgun enthusiasts. So what is your reasoning for saying it makes no sense?
Also, it is not necessary to stand awkwardly or lean forward to shoot out the window at either the Z133 or Z124 target. My experiment and photos show that to be true. Even if it was an awkward shot, he shouldn’t have missed the entire limo if it was an intentional shot without interference from the window box or the metal conduit. He was an ex-marine after all.