There is no proof that Sirach was written before Jesus Christ showed up...It is more likely that the author of Sirach copied from the book of James...
There was no such consensus among Jews that the OT Canon was closed until long after Christ's Ascension and Pentecost and even the Destruction of the Temple, when Jewish authorities would have no say so on such things.
There was a consensus of at least one Jew...
Luk_11:51 From the blood of Abel unto the blood of Zacharias, which perished between the altar and the temple: verily I say unto you, It shall be required of this generation.
Luk_24:44 And he said unto them, These are the words which I spake unto you, while I was yet with you, that all things must be fulfilled, which were written in the law of Moses, and in the prophets, and in the psalms, concerning me.
Jesus left out the apocrypha....He never taught a word from it...The canon accepted by Jesus is the Law, the Prophets and the Psalms...
fThree copies of it are among the Dead Sea Scolls all of which have been dated as havng been wrtten prior to the birth of Christ.