This attempt at refutation by Trent Horn is ridiculous and manufactured. The translator of Ecclesiasticus in no uncertain terms distinguishes "these things" (meaning the work that he is translating) from "the law and the prophets and the others that followed them." Thus, he believed that there was a threefold structured collection of sacred books that were accorded a unique status. Even the last of the three divisions of the Hebrew canon is spoken of in this passage as being "of our ancestors." Thus, this process was not going on in the days of the person translating this work or even his grandfather. This description suggests a closed canon.
"According to Old Testament scholar Otto Kaiser, the deuterocanonical books “presuppose the validity of the Law and the Prophets and also utilize the Ketubim, or ‘Writings’ collection, which was, at the time, still in the process of formation and not yet closed.” In fact, the Dead Sea Scrolls, which contain Jewish writings from the years 400 B.C. to A.D. 100, include copies of deuterocanonical books like Sirach, Tobit, and Baruch, which shows they were considered to be part of the Writings."
Hundreds of manuscripts of non-biblical material have been discovered in the Qumran caves. It was comparable to a library which contains several different genres of literature. So one cannot simply appeal to the Dead Sea Scrolls as grounds for including the apocrypha in the Old Testament canon. These people were educated in the literature of their time and would have known books such as Sirach and Tobit.
"Hebrews 11:35 describes people in the Old Testament who “were tortured, refusing to accept release, that they may rise again to a better life.” These people are only described in 2 Maccabees 7, which describes brothers who accept torture instead of eating pork and violating Jewish law. Since the context of Hebrews 11 includes “the men of old [who] received divine approval” (v. 2), this means the books describing the Maccabean martyrs were part of the Old Testament that was used by the author of the Letter to the Hebrews."
The author of Hebrews could have referenced the Maccabeean Revolt for the reason this rebellion took place in more recent history and not that he ascribed canonical status to 2 Maccabees. It would make sense for one to consult that work for historical purposes due to that event having a particular significance to an audience with a Jewish background. Furthermore, there could have been multiple sources or family traditions from which the author of Hebrews gathered his information.
"The idea that the early Church viewed the deuterocanonical books as Scripture is even more evident in the writings of early Church fathers like Clement of Rome, Irenaeus, Athenagoras, Clement of Alexandria, Methodius, Cyprian, and Origen. Moreover, these fathers cited these books as “Scripture” or “holy Scripture,” and none of the pre-Nicene Church fathers ever declares the deuterocanonical books to be uninspired or non-canonical. St. Jerome even tells us that at the Council of Nicaea the deuterocanonical work of Judith was considered to be a part of the canon of Scriptures."
There were church fathers who were not familiar with the Hebrew canon and so mistakenly thought the deuterocanonicals to be inspired Scripture. A distinction was made between the canonical books of the Old Testament and the deuterocanonicals as early as the second century which lasted until the timing of the Protestant Reformation. Bruce M. Metzger writers: