I haven’t seen the video of this person - is it HIS filming of hurt people, or is it a video by someone else showing him walking around with his phone? If the later - he might have just been using the flashlight feature to check people’s injuries. Or having it on video so he can use the light.
Liveleak had it. FR Tigerclaws posted the link.
It may have been a friend following him that was recording the events.
While he appeared young and drunk, he was genuinely trying to locate people that had been left to die. The authorities blacked out the parking lot and he was begging them to light it up and continued to search for possible live victims.
The guard argued with him. Nearly all were dead, but a few may have survived. Very tragic and gruesome video.