Jim sure made it easier for Cochran by calling him a coward so vehemently twice.
One could attribute Jim's passion just to the heat of the moment, and maybe think that Cochran didn't get treated as badly as he said. I know how these shows can do their edits so maybe we saw every bad and semi-bad moment and he was treated better off camera. ... but remembering how he had been treated was bad enough to bring Dawn to tears so apparently it was pretty bad
... so .... welll ... just yay for Cochran. He made a big move. He should live to fight many more days due to this move. Good for him.
. . .or. . .(I used to write murder mystery stories with a twist ). . .when Cochran said he would explain later, he could also be intentionally winning the Upolu tribe confidence and trust to enhance his role as double agent. I won't be entirely blind sided if that happens either.