I think it’s fair to say that Matthew 26:24 has never been infallibly interpreted to imply that Judas ultimately was condemned to hell.
However, the statement “better never to have been born” could imply damnation, in light of the idea that eternal punishment could be seen as being the only thing worse than never having existed. (Someone far more qualified than I am would have to actually expound that idea, which may or may not be theologically valid.)
Indeed, no less an authority that Avery Cardinal Dulles
once opined that “several statements [in the New Testmant] about Judas can hardly be interpreted otherwise [than to say he was damned].”
Now, Cardinal Dulles is not the Magisterium, but it’s fair to say that his opinion is at least probably one that is acceptable for a Catholic to hold.
I think, therefore, you may be making your case a bit too strongly.