Both videos show the first expolsions are all right of building center. Big expolsion comes from center of building. One small explosion left of center and outside of where left wing entered. Purple color indicates potassium explosive, althouth there's a little red in it, which would be possible potassium/strontium combination, maybe 95/5, 90/10. Left wing disappears with no damage to building, next frame engine visible, but no wing between left engine and fuselage. Right and left eleavators disappear and reappear. Engines were aligned with first 2 small explosions. Four explosions from below both camera views of towers, 3 before strike, 1 during. Purple and yellow green light flashes from below visible in pics, watch sky color.
https://www.youtube.com/watch?time_continue=28&v=7Ie_An382Fk