I have just finished reading the almost 200 page diary of Ensign George Henshaw, who was captured on Wake and ended up working with Provoo, broadcasting for the Japanese.
It was considered
force majeur and so the POWs who did this were not prosecuted.
However, Provoo was a different story. The diary is filled with examples of how Provoo aided the enemy - including acting as an informer.
June 20, 1944: Provoo must be stopped. He is deliberately putting ggreat danger the lives of his fellow men, steals from them, reports their activities to the Japs ...
- Page from Henshaw diary
I am not surprised he was convicted of treason. The sentence was overturned on a technicality - the defense felt that his homosexuality was improperly mentioned by the prosecution. As an aside, he did pursue an unwanted and unwelcomed relationship with another POW.
Henshaw mentions how one senior officer in an earlier camp told his men that anyone who put Provoo "out of the way" would be in the clear as he would accept full responsibility