Neither you nor your source can produce definitive evidence of what you are claiming. It is just your (and his) opinion (unless you are an authority on the "pure" Septuagint).
From wikipedia:
The 3rd century BCE is supported for the translation of the Pentateuch by a number of factors, including its Greek being representative of early Koine Greek, citations beginning as early as the 2nd century BCE, and early manuscripts datable to the 2nd century BCE. After the Torah, other books were translated over the next two to three centuries. It is unclear which was translated when, or where; some may have been translated twice (into different versions), and then revised. The quality and style of the translators varied considerably from book to book, from a literal translation to paraphrasing to an interpretative style.
The translation process of the Septuagint and from the Septuagint into other versions can be divided into several stages: the Greek text was produced within the social environment of Hellenistic Judaism, and completed by 132 BCE. With the spread of Early Christianity, this Septuagint in turn was rendered into Latin in a variety of versions and the latter, collectively known as the Vetus Latina, were also referred to as the Septuagint initially in Alexandria but elsewhere as well. The Septuagint also formed the basis for the Slavonic, Syriac, Old Armenian, Old Georgian, and Coptic versions of the Christian Old Testament.
I am not accusing you of lying. I am simply stating that you are wrong in your assumption. Lying is knowing the truth but deliberately stating otherwise. Why are you so touchy?
