It was a Nissan Patrol and he was locking the hubs. If here were a little bit late he would have no chance to walk up close to the vehicle as the water was very fast and rising more than ankle deep.
That vehicle will not float easily, but we should not compare this situation with casual off-road wading or fording. There is a huge amount of fast moving water involved.
He used his chance to be there on time and do the right thing to save his vehicle. 30 seconds later the black BMW next to his Nissan began to drift slowly by the force of the flood and the two other cars that strated pushing it.
I often cross moving water with my Land Rover and it can be very tricky to keep control of the vehicle while doing it.