Question about last quarter of the movie

I just saw this movie again since it came out and I never read the book. So I have to ask was the calamity which happened to the husband suppose to be funny? I thought it was hilarious and could of came from another movie or made a movie of its own from this story alone.
If a comedian played the part I am sure it would of be considered a comedy. Who does this happen to in a serious movie? It was so out there outrageous it had to be funny.

First Tony gets sick then all of the people who were guiding them through the jungle fled when they saw the mechanical mouse even though the explorer thought they would love it. Then they steal everything from the camp later. He gets sicker and the other guy loses the boat and falls down the waterfall which he was warned about when he asked the name of the stream. The woman kept on saying no name it waterfall. But obviously he doesn't listen. Then Tony gets saved by Alec Guiness who claims to be a Barbadian and tribe member. I never read the book but I didn't believe that. WHo nurses him back to health but keeps him there so he can read to him. And in the end gets declared dead because they had some cerimony to put him to sleep for a couple of days and they showed proof he was there and had died. What a bunch of trouble. Did the book explain Mister Todd more we see in the movie?
In the book did he explain who Mr Todd was. I remember a few lines when he said he read something. SO could he really read or was he using that as a excuse?