As someone who considers myself a "recovering Christian", I love asking this question of self-righteous Christian folks when they try to engage me about Christianity. It brings up the contradictory issues of predestination vs. free will, along with the question of the Christian God being both all-benevolent and all-powerful. My argument is basically that in either case, Judas is the hero, not the villain, of Christianity.
If Judas was predestined to betray Jesus, he fulfilled his role as part of God's plan. (This doesn't mean he escapes the guilt for playing what felt like an evil role -- which led to his suicide in the story -- but he shouldn't be damned for doing what God wanted/created him to do).
If Judas betrayed Jesus by choice, then he still fulfilled the role of ensuring the Crucifixion/Resurrection/blahdeblah all happened. The fact that his free choice led to something evil in the service of good shouldn't matter, any more than all the folks killed by God's chosen people throughout the Old Testament in service of whatever goal.
Whether he chose it or not, Judas set the whole convoluted plan of God's in motion. While he may have suffered guilt around the consequences, it really would run counter to God's supposed benevolence to say such a person would be guilty enough of anything to be damned. He did less "evil" things (i.e. killing, adultery, etc.) than most "heroes"/protagonists of the Old Testament did.