Most likely Hebrews from the Dispersion still living in Persia, or, “Beyond the river.”
I don't think so, because Hebrews of the Babylonian Shul would not have needed the Micah 5:2 reference. They would certainly have anticipated the Bethlehem location. But if they were Syran, they would not need a transltor, either; and id they were of the pre-Noah-origin wisdom, they might well be of the Padan-Aram location.