I enjoyed your response to Explaining the Transfiguration. Although I have never thought of that way, I appreciate the added insight. I always understood that passage to mean that Jesus was referring to the Apostle John. Of course, John was the only apostle who died of natural causes, but was privileged to be the recorder of Christ’s revelation, and therefore saw Him in the future on His throne before, during, and after the Earth’s judgments commenced.
You make a good point, and had Jesus said “I tell you the truth, one who is standing here …” instead of “I tell you the truth, some who are standing here will not taste death before they see the Son of Man coming in his kingdom” yours would be the most likely interpretation of the event. But as it’s stated it Matt. 16:28 requires multiple witnesses.