His CO agrees...
The penalty for desertion in combat is imprisonment or death...whether or not the deserter was a traitor.
I imagine there might be evidence that Bergdahl did not collaborate with the enemy, but anything could be staged once he was with the Taliban.
That report might “say” that he was not a traitor, but there is no way to prove that he was not a traitor. And picture or stories of him with the Taliban either carrying a weapon or engaged in training or going on a mission are all evidence that he very well might have been a willing participant.
But we should not allow a desertion to go unpunished just because no one can prove collaboration with the enemy. An Army cannot have its troops deserting and fabricating stories. The desertion MUST be punished, and the punishment must have teeth.