Much as these passengers would tell falsehoods about being a mile-and-a-half from shore, or even 500 yards from shore, the pre-planned nature of this exercise tells us, just as the salvage company owner said, "The plane was found 200-300 yards from shore," very near where it first when down.
And within 200-300 yards from shore, as Butterdezillion alluded, was an area very near to the point of ditching where the NTSB's bathymetric map shows the bottom to have been a mere 1 meter deep. From that point, the passengers could have swum if not walked to shore.
The satellite image above middle shows the bottom had alternating very shallow areas that contained some sunken pools. A person could be videoed with 20' of blue water apparently all around, then moments later with two dog-paddle efforts, be standing on the ocean floor to rest from any stress or acting.
In the four, upper-left images, we see Flip is able to stand in many places throughout the scenario, spanning from the very first few minutes after ditching to an hour later, as he walks the last 30 yards to dry land.
In the image immediately below that of Rosa in the upper left image, we see Flip Hollstein had no trouble keeping 12-14” of his torso above water while standing straight up, just five yards or so from the airplane
The Deputy Health Director is seen in the lower left two pictures to be able to stand while he was within inches of Ms Fuddy. Also knowing that skilled, professional, US Navy-trained divers were just yards away, would that be a place one could expect to be fearful, hyperventilate and have a cardiac episode?
In the lower middle, see how much of her body Rosa Key is able to keep above the water line! Knowing of the nearby presence of US Navy divers and how the HDOH DD could stand so near to Ms Fuddy should tell us all we need to know and whatever else was left to guess about how stressful this scenario needed to be for Ms Fuddy.
Though Mrs. Key was quoted in the media, saying she and her husband were badly shaken and traumatized during the event, there’s also a lot of evidence to the contrary in the videos.
On the lower right we see images of the videographer being able to stand on the ocean floor as well.
In one interview, Passenger Bruce Briley—who never was said to have made it near shore—was asked how the ocean floor there was to stand on; he said, without hesitation, “Squishy.” (See him standing just to the right of the middle of the collage, while he was just a few yards from the plane. How do you suppose the world will think he was able to keep two foot of his torso above water?
Though Hollstein choose to walk the final yards to shore, the Keys, the videographer and Yamamoto just waited near shore to be helicoptered out of the water, despite there being evidence they could touch bottom, and that they, too, could have walked out, if they’d been so inclined.
It took one helicopter only 14 minutes to bring all four of those passengers (the videograph, the HDOH DD, and the two Keys) waiting in the shallows, one at a time, to shore.