From “JustforCAtholics.org”
Question: St Jerome was persuaded, against his original inclination, to include the deuterocanonicals in his Vulgate edition of the Scriptures. What are your comments?
Answer: True, yet he classed the Apocrypha in a separated category. He differentiated between the canonical books and ecclesiastical books, which he did not recognize as authoritative Scripture. This is admitted by the modern Catholic church:
“St. Jerome distinguished between canonical books and ecclesiastical books. The latter he judged were circulated by the Church as good spiritual reading but were not recognized as authoritative Scripture. The situation remained unclear in the ensuing centuries...For example, John of Damascus, Gregory the Great, Walafrid, Nicolas of Lyra and Tostado continued to doubt the canonicity of the deuterocanonical books. According to Catholic doctrine, the proximate criterion of the biblical canon is the infallible decision of the Church. This decision was not given until rather late in the history of the Church at the Council of Trent. The Council of Trent definitively settled the matter of the Old Testament Canon. That this had not been done previously is apparent from the uncertainty that persisted up to the time of Trent” (The New Catholic Encyclopedia, The Canon).
http://www.taylormarshall.com/2011/09/did-st-jerome-reject-deuterocanoical.html
Neither "JustforCatholics.org" and the New Catholic Encyclopedia are inerrant, nor necessarily scholastically authoritative. I do not know a single theology or Church history that would accept them as a valid source.
In reality, St. Jerome did state that he knew of no Jews who considered the Deuterocanonical books as a part of Jewish canon or Scripture, but St. Jerome was not asked to second guess or validate the decisions of the Council of Rome or the directive of his Pope to translate the listed books. He stated numerous times in his later writings that he did consider them to be Scripture.
Peace be with you