Man... that outcome is pretty fucking contrived.
Let us just add the necessary factors together...
#1. Uncle's team being ocean-hunting at the same time on the same day as they were going there.
#2. Uncle's team having difficulty with the whale they were hunting and needing to drag the others in to help.
#3. The whale choosing to escape in that particular direction.
#4. That ONE guy getting knocked into the water by the whale.
#5. The only person who could identify the guy being on the other boat and going away with the whale.
Yeah... this is a pretty fucking contrived encounter.