I probably can't provide much, but my investigations have shown that there were only a few families of Alexanders in the area near Christian County KY before 1810. I know of brothers Matthew and William, Ebenezer (possibly their brother), Zenas, and John (probably related to one of the other families). Your Moses was not Matthew's son, and no one appears to have attributed him to Ebenezer. If, as many claim, William's and his brothers' grandfather was Moses, William could be the father. William was born about 1758-1760, and his wife was Esther McMillin, but I don't know much more. If John was brother to Matthew and William, he was probably born after 1763.