regarding richards advancing age---he was younger than many of our age. active and loved sailing. he had a goal-- his goal was to get to hiva oa solo.
he was driven to do puddlejump by his own motivation and will. he had a very active inner child and used that to his advantage.
regarding the possibility of co poisoning--that is a reality to which all sailors with auxiliary engines need to address. this was figured by his feeling bad inside boat
and better when outside boat
. this was in his interactions with his family
. i believe it was also mentioned in the article.
this has been most difficult on his family as there was no closure. he merely vanished off face of planet. here today and then gone.