The earliest church patriarchs, such as Origen, Pliney and Trajan always pointed to Cannon.
While the didache is attributed to this time period, it is more an instruction manual not scripture. Because of that, it holds no authority other than what man places in it.
It is true that all the Church Fathers appeals to Scripture, but related to Church Discipline the authority of the Bishops and other Church Leaders were in charge.
Origen also, quoted books you do not believe to be Scriptures:
"5. But that we may believe in the authority of holy Scripture that such is the case, hear how in the book of Maccabees, where the mother of seven martyrs exhorts her son to endure torture, this truth is confirmed; for she says, I ask of you, my son, to look at the heaven and the earth, and at all things which are in them, and beholding these, to know that God made all these things when they did not exist. In the book of the Shepherd also, in the first commandment, he speaks as follows: First of all believe that there is one God who created and arranged all things, and made all things to come into existence, and out of a state of nothingness. Perhaps also the expression in the Psalms has reference to this: He spoke, and they were made; He commanded, and they were created. For the words, He spoke, and they were made, appear to show that the substance of those things which exist is meant; while the others, He commanded, and they were created, seem spoken of the qualities by which the substance itself has been moulded."
CHURCH FATHERS: De Principiis, Book II (Origen)
Origen appeals to those who have apostolic authority by succession:
"He has but just now found his way to the catholic fold to get healing and safety; you have a rank among the very shepherds of that fold. But we would not that a sheep which comes to the Lord's flock for shelter from error, should be healed of his sores in such a way, as first to infect and destroy the shepherd by his contagious presence.
Chapter 7.— To Think the Soul Corporeal an Error.
But if you say to me, He has not taught me this; nor have I by any means given my assent to this erroneous opinion of his, however much I was enchanted by the sweetness of his eloquent and elegant discourse; then I earnestly thank God. Still I cannot help asking, why, even with kisses, as the report goes, you expressed your gratitude to him for having taught you what you were ignorant of, previous to hearing his discussion. Now if it be a false report which makes you to have done and said so much, then I beg you to be kind enough to give me this assurance, that the idle rumour may be stopped by your own written authority. If, however, it is true that you bestowed your thanks with such humility upon this man, I should rejoice, indeed, if he has not taught you to believe the opinion which I have already pointed out as a detestable one, and to be carefully avoided as such. Nor shall I find fault [IV.] if your humble thanks to your instructor were further earned by your having acquired from discussions with him some other true and useful knowledge. But may I ask you what it is? Is it that the soul is not spirit, but body? Well, I really do not think ignorance on such a point is any great injury to Christian learning; and if you indulge in more subtle disputes about the different kinds of bodily substance, I think the information you obtain is more difficult than serviceable. If, however, the Lord will that I should write to this young man himself, as I desire to do, then perhaps your loving self will know to what extent you are not indebted to him for your instruction; although you rejoice in what you have learned from him. And now I request you not to feel annoyance in writing me an answer; so that what is clearly useful and pertinent to our indispensable faith may not by any chance turn out to be something different."
CHURCH FATHERS: On the Soul and its Origin, Book II (Augustine)
"Now this is quite a novel idea, and foreign to the Church's discipline and the rule of truth: and yet, when daring to propound it in his books, he does not modestly say, I rather think; he does not say, I suppose; he does not say, I am of opinion; nor does he say, I at least would suggest, or mention — but he says, I give it as my decision; so that, should we be (as might be likely) offended by the novelty or the perverseness of his opinion, we might be overawed by the authority of his judicial determination. It is your own concern, my brother, how to be able to bear him as your instructor in these views. Catholic priests, however, of right feeling (and among them you ought to take your place) could never keep quiet — God forbid it — and hear this man pronounce his decisions, when they would wish him rather to recover his senses, and be sorry both for having entertained such opinions, and for having gone so far as to commit them to writing, and chastise himself with the most wholesome discipline of repentance. Now it is, says he; on this example of the Maccabees who fell in battle that I ground the necessity of doing this. When they offered stealthily some interdicted sacrifices, and after they had fallen in the battle, we find, says he, that this remedial measure was at once resorted to by the priests —sacrifices were offered up to liberate their souls, which had been bound by the guilt of their forbidden conduct. "
CHURCH FATHERS: On the Soul and its Origin, Book II (Augustine)
Origen appeals to the Pope and Councils:
"Chapter 17.— Disobedient Compassion and Compassionate Disobedience Reprobated. Martyrdom in Lieu of Baptism.
The new-fangled Pelagian heretics have been most justly condemned by the authority of catholic councils and of the Apostolic See, on the ground of their having dared to give to unbaptized infants a place of rest and salvation, even apart from the kingdom of heaven."
CHURCH FATHERS: On the Soul and its Origin, Book II (Augustine)
Point is if one takes the time to search thought Origen, Pliney and Trajan --- they will likely find similar results.