Quote: but eyewitness accounts can be a very useful
I disagree. I've served on juries and eye-witnesses are highly overrated. A competent defense attorney can reduce them to blubbering piles of goo on the witness stand because most people are about as observant as a loaf of bread. The forensic evidence is always more damning.
The fact that these guys were in the lobby - so they say - and survived is ample proof that what they heard were not explosions from a controlled demolition. They would have been killed when the building fell down on their head.