Sorry for the incident and glad to know that you are safe. Based on the video, i personally think that a longer approach was needed to climb especially when you have a heavier vehicle. The approach and angle to climb the dune look sharp, it was a too sudden climb to actually gain enough momentum to slide slope, criss cross or ridge ride.
You will notice there was another track few meters before you started the climb, it is better to take a smoother path by starting to climb earlier and gradually with enough momentum. If there is a loss of momentum and if you are fishtailing, steer down smoothly towards the tail and descend. Lastly, in such situation, sudden turn and brake are very risky.
Thank you for sharing the video @Zed, so we all can keep learning...