> Wasn't it mounted on the plane dash, and he took it with him when he bailed?

I had the exact same thought. If you look at 3m53s in the video, he has both a camera in his hand and the other GoPro remains on the dash.

> Is this because he is already a skydiver and/or was going paragliding (is this the same rig? Another thing I don't know). Would it make sense that this is just "what he has," as opposed to owning both a bail out and a sky diving kit?

Another set of comments discuss that traditionally pilots who might consider using a parachute generally bring a different type of parachute on board, and not one that would be used by normal skydivers: https://news.ycombinator.com/item?id=29730298