That account matches almost perfectly the version I heard from a retired law enforcement officer within days of the incident. His son works in LE in St. Louis (I’m two hours away) and that’s the story he heard.
I believe the final stamp on this story is the autopsy report (if it shows the angle of the shot and how close the kid was to the cop), and the toxicology report. If the kid shows weed and PCP in his system (my suggestion) then he was likely under some influence and not clearly able to think. It’s hard for a jury to find any way to convict the cop at that point.
I feel sorry for the kid. But stupidity and drugs...gets you dead.
There is more information coming out. Looks like it matches what you heard.