The Gemara in Megillah 9a tells the story of Ptolemy forcing the sages to translate the Torah. Does anyone know of other accounts of this story. I'm especially curious why Ptolemy had the Sages separated to translate independently. In the version of the story recorded by Aristeas, he says that the Jews translated the Torah voluntarily. The Yaavetz to Megillah says that is a different story than the one in Megillah, although he seems to contradict himself in his commentary to Maseches Sofrim.
In addition, Maseches Sofrim seems to imply that the tragedy of translating the Torah was not the translation of the seventy sages but an initial attempt by five other sages. This seems to contradict other sources that the tragedy was the translation of 70.
Can anyone shed any light on these issues, or just refer to other sources beyond the ones I quoted?