Dylan’s hesitation?

A stampede was under way. The lunch crowd had panicked. Most took cover under tables; some ran for the stairs. About 100 were caught on the staircase, racing for cover on the second floor. Dylan took a few steps and lifted his weapon to firing position. For the second time, he appeared to lose his nerve. He swept his rifle in an arc across the room. He watched the students disappear up the stairs. He did not fire. Instead he rejoined Eric at the top of the external staircase.

It’s not clear why Dylan made his excursion into the cafeteria. Perhaps to see what went wrong with the bombs? But he never went near them. He made no attempt at detonation. It’s more likely that Eric sent him in to build up the body count.

The Guardian, Dave Cullen

Klebold, who had just shot Rohrbough and Kirklin, stepped over Graves, now playing dead in the doorway. That probably saved his life. The gunman briefly went into the cafeteria, holding his weapon in what some described as a “ready-to-fire” sweeping motion. He did not shoot but looked around and then walked back outside and returned to the top of the steps.

By the time Klebold stepped over Graves and briefly walked into the entrance of the cafeteria with his guns, most students had evacuated. Others were hiding under tables or had sought refuge in the school pantry, the refrigerator or kitchen area. Because Sanders had instructed the kids to hide or get out, the cafeteria appeared to be empty.

Klebold turned around and walked back outside, stepping over Sean Graves, and joined Harris back at the top of the stairs. The gunmen continued shooting their guns, lighting pipe bombs and throwing them into the senior parking lot or onto the school roof, while shooting toward the ball fields where students were fleeing.

CNN.com – Jeffco Findings of Outside Events

Is this truly confirmed in the 11K by witnesses that Dylan swept his Tech-9 at the mass exodus of students on the steps and in that moment, refrained from shooting? If so, which students reported this?