I don't have special insight into who might have won, just speculation from viewing the show.
I think the two top chances are Bryson Klein and Charlie Robbins. I put Bryson slightly ahead due to experience and we know he can do the stage 4 rope climb as he did it on USA vs World. Matthew Bowles would be my third pick as he does seem to be extremely strong even if it is his first season.
Others I could see doing it are Zak Stolz, Jordan Papandrea, Rob Paterson and Fred Dorrington.