From what I've learned, you aren't too far off. It has been theorized by religious scholars that the Jews picked up a few key concepts from Zoroastrianism during the Babylonian Exile. Nebuchadnezzar II forced the Jews to leave Judah in several waves during his reign. They would relocate to Persia, and during their time there would exchange certain cultural ideas, particularly Zoroastrianism's strong emphasis on dualism (good vs. evil). When Cyrus allowed the Jews to return to Judah, they brought those ideas with them. That is likely how the concept of Sheol (Limbo) morphed into Gan-Eden (Paradise/Heaven) and Gehennom (Hell), and how the notion of a supreme good force battling with a supreme evil force for the souls of humanity were incorporated into what are commonly referred to as the Abrahamic Religions.