Let me just clear something up for you. I'm not trying to be mean. In the middle of the pit, where the ball is, there are 2 vents on either side of the ball. These vents cause you to fly high into the air and randomly land in a location. Sometimes you can land on the upper catwalks.
Just to be clear, are you sure this person didn't walk over one of these vents? If they didn't, then it's a bug.
-Jade