With your mind already made up, you don't notice the obvious reasons why people talk of "explosions" and such.
In this video, from about 0:10 an (probably depending on your speaker settings), you hear the growing rumble of the gravitational collapse, as is familiar from videos of many controlled demolitions. What is notably NOT present is the sound of - explosions! If you watched any videos of real CDs, you'd know that the blasts that kick off a CD are MUCH MUCGH LOUDER than the noice of the collapse itself.
The guy is obviously confused: He sees the billowing and growing dust cloud from the collapse growing to the right of the towers, where he has a clear view, and simply misses the fact that it's one of the towers that collapsed. He says "explosion", because he hasn't hit upon "collapse" yet, and that't what it LOOKS like to him.
As for the "reverberations": The collapse released the equivalent of 100 tons of TNT and turned it into kintetic and seismic energy, the reverbereation of which travel at about the speed of sound.
Surely you wouzld expect 300,000 tons of building mass falling an average of 200 meters to reverberate in appreciable ways.
Nothing in the video is evidence for explosions, the mistaken interoretation of the reporter notwithstanding. But some things in the video are evidence that there are very likely NOT explosions of the kind that could bring down the tower CD-style.
David Lee Miller describes hearing "a very loud blast, explosion, we looked up, and the building literally began to collapse".
Fair enough.
Tghe problem is: Your first video proves Miller wrong! There WAS no such particularly loud blast sound at the beginning of the collapse, just a growing rumble. Surely, from up close, the beginning of the rumble would be a scary sound, and it isn't too surprising that, a minute of armageddon later, an eye witness would have inflated that starting sound to "blast".
The problem is: We have sound records of this event, and they show NO explosion to be heard.
While hunting for gravity collapses I found the above.
I guess the newsmen imagined the explosions.
Your guess is correct, or rather, they made an error of judgement, as they were non-experts faced with a novel situation.