By the sounds of his story, he and the 20~ that were in the alleyway assumed there were multiple shooters as he heard 30~ rapid gunshots, nearing and getting louder. He then explains that people started to flee through the fence. It seems like a quick reaction, and it would make sense at that point to protect yourself and the others alongside you with the door if it felt the shooters were immediately behind you.
Never been in that situation, but seeing the tears in his eyes, it was obviously a decision made at the time and making him feel guilty won't do anything at this point.
MANY more lives could have been saved
