I don't believe Judas was ever a part of the Body. He even resented the squandering of money for perfume. And who knows what else. I think he was very secular and never understood Jesus' mission.
Funny. I see the exact opposite.
Judas was 'chosen' to be a disciple, by Jesus no less.
John 6:70
Jesus answered them, Have not I chosen you twelve,
and one of you is a devil?
Let's see? Hmmm? I wonder "who" the devil was? Was it Judas?
Luke 22:3
Then
entered Satan into Judas surnamed Iscariot, being of the number of the twelve.
It would pretty easily appear to ME that Satan was the devil among them, in Judas. Not Judas himself.
Now, just how did that happen I wonder?
Mark 4:15
And these are they by the way side,
where the word is sown; but when they have heard,
Satan cometh immediately, and taketh away the word that was sown
in their hearts.
Were the other disciples exempt? Uh, no. Read 1 John 3:8 and we'll see that their own sin is likewise, "of the devil" along with everyone else who has ever lived on this planet except for Jesus.
Will Judas be in heaven? I think a open and shut case is made by Paul in Romans 11:25-32, clearly, that answer being a resounding YES! Because Judas was an Israelite and "all" of Israel shall be saved, even enemies of the Gospel. Says so right there in Romans 11:25-32. So who would not be saved in these equations? Uh, Satan. See Romans 11:8 for the same picture on unbelieving Israel.
It's all in how gracious one is LED to see my friends.
And, in addition, Judas really didn't stand much of a chance. What he did was written about in the Psalm, 41 specifically, long before Judas was the proverbial glint in his fleshly fathers eye. Could Judas have done differently? Uh, no. Because it was not just Judas involved, but SATAN. And God certainly knows what Satan in man will do. IN advance, even.