Re: When did he know and when did he know it?
I'm far too tired to look deeply into your sources, but even a cursory examination shows that these crack journalists told us that in 1945, a B-52 crashed into the Empire State Building (link under your point #4...the other link appears dead).
A slip of the tongue? A typo on the website? Maybe. Maybe not. Perhaps the journalist were engaged in that time-honored TV news tradition of blathering on and on to avoid dead-air, all the while not particularly giving a damn about trivialities like fact or sequence of event.