Yacht's crew unable to climb back aboard


Watched a disturbing film last night: Adrift, which, according to the producers, is based on real events. A 60ft sloop, Godspeed of San Diego, puts to sea from a Mexican port with three young couples aboard. Once a day or two out from the coast, with sails furled and engine off, but with no anchor down, they all leap over the side for a bathe.
Only when one of their number starts getting cold do they realise they have not put down the automatic gangway: there is no way back aboard as none of the very fit young men can reach the gunwale some 11 feet or so above them.
As they start to die off: from hypothermia, concussion, and an accidental stab wound and one swims away to her doom, I was pacing the room wracking my brains as to what I would have done.
I came up with this: just one of their number is wearing a lifejacket, another of them has a heavy scuba-diving knife. All are wearing swimming trunks or bikinis. I would have stripped the lifejacket of its webbing belt and crutch strap – maybe have halved the belt along its length with the knife. Then using either a drawstring from one pair of trunks or a strap from a bikini, I would have lashed the knife to the loop in the bitter end of the lifejacket crutch strap. Next having knotted the lengths of webbing together I would have hurled the knife at the pushpit (lower down than the pulpit) endeavouring to get the knife over the lowest rail. Once over I would have lowered the knife back to the water, unbent it and put a bowline on the bight around the standing part of the webbing, pulling the knot tight to the rail. Then, with the three lads as a swimming triangle base would have encouraged the lightest girl up on their shoulders and then hand-for -hand up the webbing.
What would you have done?
Answers on a postcard please.