It’s 3 AM and I just realized something and solved a murder mystery I didn’t notice happened for years:
Jenkins didn’t murder Leeman Kessler.
Leeman Kessler murdered Jenkins.
He came into contact with a grand relic, the only person besides Merle, Taako, and Magnus to do so and not be over powered by it’s thrall?
Nope.
He was overpowered by it, knew the regulators would be after him if he used it or tried to keep it, and came up with a plan.
He killed Jenkins, then used an illusion to disguise Jenkins’ corpse as himself, and used the oculus to make the illusion real. Then used an illusion to disguise himself as Jenkins, followed by using the oculus to make that illusion real too. Effectively switching places in a way no one could trace.
That’s where everything went wrong.
The oculus makes any illusion become real, so when Leeman became Jenkins, he became Jenkins completely and was no longer Leeman, memories, abilities, and motivations included. Leeman Kessler was gone. He. Was. Jenkins. But not quite. Leeman, a half elf, botched the illusion, which is why Jenkins had a mustache, couldn’t get his own voice right, and basically had that existential meltdown. Since the illusion wasn’t perfect, the Jenkins that was alive and on the train (The real Leeman) wasn’t mentally a perfect Jenkins. The voice and meltdown were a glitch caused by imperfect illusion.
Leeman didn’t realize what his disguise would do to his mind after using the oculus, or that the real Jenkins was also the serial killer, The Rockport Slayer. He didn’t remember the oculus or that he was Leeman Kessler. When he made the switch, he would have just thought that he, (Fake Jenkins) had killed the real Leeman Kessler (Real Jenkins) as The Rockport Slayer. Leeman then continued living the next day as Jenkins, continuing Jenkin’s killing spree as The Rockport Slayer, commiting a crime almost identical to the switch he already pulled before getting caught and dying as Jenkins.
And in death? The real Jenkins is enjoying Leeman Kessler’s after life, While the real Leeman Kessler is in the eternal stockade serving Jenkin’s sentence AND KNOW ONE KNOWS ABOUT ANY OF THIS!