...returning to the subject...
First, this is a"photoshoot", but
nobody is smiling for the camera.
But this proceeded badly anyway: to the right in the frame, an over-sized boat has made a big wake that is "curving to the inside" of the 38 Fountain. (The steepest—and most "impact-worthy" type of wake).
Another clue is that the Captain was
working the throttles to "get-air" over each wave. Some viewers have characterized this as "showing off".
He's in trouble here—notice
the horizon.
...and this is a photoshoot, where smiles were
already absent!
He "got air" twice, then the boat landed badly—on its side—producing this:
In the final frame, as the 38-Fountain's bow gets a "stuff", the camera records the Fountain's wake—which indicates a very high speed even after the landing—and everyone aboard is thrown
forward.
Lastly, the passenger to the right is thrown forward against the two other victims—
increasing their injuries—but unintentionally lessening her own injuries.
As for "sitting down", many passengers don't like the jarring and hammering movements of a boat affecting their spine.
...Jet-Skis in rough water, especially...
As it was, two aboard were reported with skull fractures (of the
orbit—the outer ridge of the eye socket).