Most stuffs been mentioned but as someone who has built and driven rock crawlers I'll chuck in a few points.
Spotter! Needed eyes outside with someone who knows their s**t. The moment the car stalled it became a recovery situation, even if he started it he wasn't going to drive it out.
Reverse key start or "recovery start" are good to look into in stalled hill situations. However only works in a manual, this looked like an auto.
Hands inside the car. Scary s**t seeing passengers arm outside. Hairy hill 101, hold onto something solid inside. Amount of people that have had arms crushed in roll overs is crazy. Reason why comp trucks require window nets.