Trev's fishfood. The only way he's gonna come back from this one is if The Goat pulls off a "Bobby's dream in the shower" trick (that's an age giveaway heh heh).
Why's he dead? Cos:
1/ the physiology for freediving records don't apply - reflex bradycardia, vasoconstriction, blood shift etc (ooooh, big words!) - due to Trev's lack of training, experience and preparation (lots of deep breaths) and panicked thrashings as he sinks to his doom.
2/ he's already been under water nearly 2 minutes
3/ he's 90' down and sinking, exhausted and cramped
4/ he's still got to free the weight belt - more seconds + depth
5/ he's still got to untie the ropes now stiff + swollen (the only thing that is!) from water immersion
6/ his hands are now cold + stiff too, and difficult to move
7/ he's in pitch black and won't know his up from down when he tries to kick for the surface
Trev's a dead parrott .. er ex-yachtsman, he is no more, he's gorn to meet his maker, he's a stiffie.