It's intriguing to see what kind of personality a billionaire has that pushes him to do these stunts and also publicly brag about them. I hope it's not a necessary ingredient to success as I do not intend to live like that.
That being said,
> He added that because the passengers were sealed inside the vessel by bolts applied from the outside, "There's no way to escape, even if you rise to the surface by yourself. You cannot get out of the sub without a crew on the outside letting you out."
ouch