Just before break-off on this 2-way belly jump, one jumper got flipped over the other right before "tracking away" — but neither jumper really tracked. When they deployed, they were dangerously close to each other and nearly had a midair collision.
The jumper who submitted the video said that the second jumper failed to turn 180 degrees away and tracked under him. However, from what we're seeing here this was really just poor tracking by both jumpers. As seen best in the second jumper's video (camera 2), the first jumper sees his buddy, waves off, doesn't really create any distance, sinks out a bit, checks his altitude, and deploys. The second jumper at least tries to track a little, but also doesn't get much distance before deploying.
We really hate using cliches on Friday Freakout, but this is one of the most important cliches in skydiving. When it comes to tracking and canopy piloting, you need to make room and consider anyone around you as a threat to your life. These two didn't create space, didn't track, and — evidently — didn't consider the other jumper an immediate threat to their life. As a result they both had super lazy tracks and opened up in each other's faces.