What other person? If your talking about the guy in the crack, in the beginning of the video it shows where he goes.

Not really, your POV vaguely shows the boomer distractor jumping off into the distance and it isn't helpful at all. Where is is exact hiding spot? And how often need he fire his weapon to keep the boomers busy? Thanks.

Okay, I apologize for that. On the boomer tower there is an outer edge that you can walk on. You walk on that edge towards the over soul (sky) and you should see a rock in your way, but you can jump over it. Just stay back there and shoot at the wall to distract the Knights. I call out for that person to shoot whenever we're running from the crystal room back out to the middle, or whenever I'm going up to smash Crota. Also you need to know that special weapons don't work, so something like Ice Breaker wouldn't work. I don't know why that is, but it just doesn't work. So I suggest that you carry something like Atheons Epilogue or Eidolon Ally because of the high ammo in reserve. Hope this helped.