Before Trent, if one insisted canonical books ought not to be in the Bible, they were heterodox. If they insisted they are not in the Bible, their assertion was incorrect and illicit (unlawful, contrary to the binding authority of the Church). After Trent, if one insists they ought not OR they are not in the Bible, they are heretical.
Cardinal Cajetan:
Here we close our commentaries on the historical books of the Old Testament. For the rest (that is, Judith, Tobit, and the books of Maccabees)
are counted by St Jerome out of the canonical books, and are placed amongst the Apocrypha, along with Wisdom and Ecclesiasticus, as is plain from the Prologus Galeatus. Nor be thou disturbed, like a raw scholar, if thou shouldest find anywhere, either in the sacred councils or the sacred doctors, these books reckoned as canonical.
For the words as well of councils as of doctors are to be reduced to the correction of Jerome. Now, according to his judgment, in the epistle to the bishops Chromatius and Heliodorus, these books (and any other like books in the canon of the bible)
are not canonical, that is, not in the nature of a rule for confirming matters of faith. Yet, they may be called canonical, that is, in the nature of a rule for the edification of the faithful, as being received and authorised in the canon of the bible for that purpose. By the help of this distinction thou mayest see thy way clearly through that which Augustine says, and what is written in the provincial council of Carthage. (Commentary on all the Authentic Historical Books of the Old Tesdtament, In ult. Cap., Esther. Taken from A Disputation on Holy Scripture by William Whitaker (Cambridge: University, 1849), p. 48. See also B.F. Westcott’s A General Survey of the History of the Canon of the New Testament (Cambridge: MacMillan, 1889), p. 475.)
It certainly appears that Cajetan says the deuteros are not in the canon. Was Cajetan (the person the pope picked to debate Luther) a heretic?
Brian