But, from what I understand, we don't know what weapon was used unless we believe in that Schrödinger rifle wrapped in a towel of same nature with creatively engraved bullets? But I didn't follow all the details closely, so may be missing something.
I don't think you are missing anything.
I think to reach some plausible conclusions people first need to agree on a few basic facts, and take that line of questioning to its conclusion.
Was he shot? Yes or no.
Was he shot at close range or from a distance? etc.
Based on the video, to my eyes, if he was shot, it looked like it was from a distance. But that creates a problem because something high calibre would have been needed, and in that case, that doesn't explain why there is no exit wound.
Okay, right, maybe he was shot from much closer and with something much weaker that resulted in the bullet not exiting the body. That leaves a conundrum though because
a) the perp would have been seen by the crowd surely
b) the angle of entry.
Are the PTB going to come out and tell us the truth? Would we believe anything they'd say anyways? The answer to the last question is
no.
So the mysteries will kind of remain for now. The answer we should accept is that he was shot from a distance but for whatever reason there wasn't an exit wound despite the bullet hitting the neck directly. And we shouldn't ask any more questions beyond that.

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