The presence of the Apocrypha in the Septuagint (i.e. the Greek translation of the OT) does not support their inspiration for a number of reasons:
First, the Septuagint was translated before the Apocrypha were even written. The Septuagint was translated between 250-132 BC, but the Apocrypha date from 180 to 100 BC! Thus Apocrypha scholar David deSilva writes, “The ‘Septuagint’ codices mentioned above cannot be used as evidence for an Alexandrian Jewish canon that included the Apocrypha.’ These manuscripts are fourth and fifth-century Christian works, fail to agree on the extent tent of the extra books, and seem to have been compiled more with convenience of reference in mind than as the standards of canonical versus noncanonical books (the fact that one even contained, at one point, Psalms of Solomon strongly suggests this). As ‘church books,’ they may have sought to contain what was useful rather than what was strictly canonical. These manuscripts do bear witness, however, to usage in the church in the fourth century (differing from one region to another or even within a single region). The fact that the books of the Apocrypha are interspersed among the (other) Old Testament books also suggests that the communities that produced these manuscripts did not share a consciousness of a closed Old Testament canon corresponding to the rabbinic canon. With these considerations in mind, we can begin to sort out the history of the use and status of the Apocrypha books in the early synagogue and early church.”[1]
Second, the complete Apocrypha are not found in any of the various codices that contain the Septuagint. Scholar D.A. Carson writes, “Although the LXX translations were undertaken before Christ, the LXX evidence that has come down to us is both late and mixed. An important early manuscript like Codex Vaticanus (4th cent.) includes all the Apocrypha except 1 and 2 Maccabees; Codex Sinaiticus (4th cent.) has Tobit, Judith, 1 and 2 Maccabees, Wisdom, and Ecclesiasticus; another, Codex Alexandrinus (5th cent.) boasts all the apocryphal books plus 3 and 4 Maccabees and the Psalms of Solomon. In other words, there is no evidence here for a well-delineated set of additional canonical books.”[2]
[1] David A. deSilva, Introducing the Apocrypha (Grand Rapids, MI: Baker Academic, 2002), Kindle Location 313.
[2] D.A. Carson, “The Apocryphal/Deuterocanonical Books: An Evangelical View.” in The Parallel Apocrypha (Edited by John R. Kohlenberger III. New York: Oxford University Press, 1997), xliv-xlvii.