Pope St. Leo the Great taught that Judas was in hell:
"The traitor Judas did not attain to this mercy, for the son of perdition (Jn. 17:12), at whose right hand the devil had stood (Ps. 108:6), had before this died in despair; even while Christ was fulfilling the mystery of the general redemption. Even he perhaps might have obtained this forgiveness, had he not hastened to the gallowstree; for the Lord died for all evildoers. But nothing ever of the warnings of the Saviour’s mercy found place in that wicked heart: at one time given over to petty cheating, and then committed to this dread parricidal traffic. … The godless betrayer, shutting his mind to all these things [expressions of the Lord’s mercy], turned upon himself, not with a mind to repent, but in the madness of self-destruction: so that this man who had sold the Author of life to the executioners of His death, even in the act of dying sinned unto the increase of his own eternal punishment. (Sermon 62, De passione Domini XI [PL 54], in The Sunday Sermons of the Great Fathers, vol. 2, p. 183)
St. Catherine of Siena also taught Judas went to hell:
"This is the sin which is never forgiven, now or ever: the refusal, the scorning, of my mercy. For this offends me more than all the other sins they have committed. So the despair of Judas displeased me more and was a greater insult to my Son than his betrayal had been. Therefore, such as these are reproved for this false judgment of considering their sin to be greater than my mercy, and for this they are punished with the demons and tortured eternally with them." (The Dialogue, n. 37, Paulist ed., p. 79)
Note in Catherine’s it’s actually Jesus Himself saying Judas is in hell.
So while it’s true that the Church has never infallible decreed a “reverse canonization” saying anyone is in hell, there is a long tradition in the Church of saying Judas is in hell.
Personally, I’ll wager with the great Saints and Doctors of the Church Leo and Catherine and believe Judas is in hell, rather than believe Judas could be in heaven which heavily implies universal salvation, a condemned heresy.