NO offense I have to answer this one. I hate answering something like this since I know my percentage will go down on being the right answer.
A hot tub will not go up to 114 degrees. So this doesn't happen. If it is an old tub it will have a high limit switch tthat at 108 will flip it off. A modern tub being one, that is electronic will not go past 104. It can creep to 105-108 max. with a direct sunlight in the summer. As far as the other answers..being his vessels were dil. they are correct. A clot could have formed or mere blackout
and therefore drowing. I am not a doctor of humans so I cannot say. But as far as the tub...You need a better teacher that is posing this question since they do not know what temps are actually involved in hot tubs. Tubs are safe.