Compare John 13:21-30
Somebody evidently needed to play Judas’s part in the drama of atonement and salvation. For that matter, I suppose that somebody needed to play Satan’s part, as well.
However, neither of them will be rewarded for fulfilling these roles.
Likewise, in order for this mortal probation to be complete there must be betrayals and unkindness. But those of us who do such things should expect no thanks for them.