5 days too late to be a joke, very impressive indeed. It does kind of read like the plot to a movie though. Let's try a trailer:
[The camera flys down into the ocean, diving deeper, getting darker.]
Voice Over: "In world, where only 5% of the oceans have been explored, two men will increase that percentage."
[Cut to Richard Branson]
Richard Branson: "We need to see what's down there."
[Cut to Chris Welsh at a dock yard speaking to an old sailor with an pipe and eye patch]
Chris Welsh: "We need a sub to get down to 37,000ft. I hear you're the man to build one."
Graham Hawkes (sub designer): "Aye, that I am, but it will cost you."
Chris Welsh: [Smiles] "Don't worry, that won't be a problem."
[Cut back to the dark ocean]
Voice Over: "Virgin Oceanic"
Now back to reality, by the sounds of it they will only have one of the subs and so no hope of rescue. How about instead of that, Richard Branson uses some of his near infinite money to build maybe a second one, or maybe two.