I do not know where I stand on the issue of Judas. Even Christ DID say that it was a betrayal (the comment he made about being betrayed with a kiss).. but then, it appears to have been God's plan. A conundrum for sure. Maybe that is exactly what the point is supposed to be...that if we follow the tenets of Christ, we will not concern ourselves with the moral issue surrounding Judas, because we know that judging him is not our place.
One could drive oneself crazy trying to figure out the whole free-will vs pre-destination thing. I do tend, however, to lean heavily towards the free-will side because without it, I cannot see how a Just God could condemn us for sinful acts. And I do believe Him to be a Just God.
Christ assuredly knew what was going to happen to him, knew who was going to do it, and did nothing to prevent it from occuring...
This is why the Gospel of Judas appears credible here. Jesus had numerous opportuntities to avoid execution, but He clearly had no interest in avoiding it. He practically welcomed it. Jesus really wanted a big show trial, with all the attendant publicity. Was Judas in on it? We will never know, but it does make a lot of sense.
Frankly the Gospel of Judas is so fantastic, it could very well be true. What would be the motivatoin 1900 years ago to make it up??