Just one more point:
Given that the other king of Geshur mentioned in the Bible, the
father of Talmai was called Ammihud ((ammiYhuWd)
http://bible.crosswalk.com/Lexicons/Hebrew/heb.cgi?
number=05989&version=kjv
HuWd meaning splendour, majesty, vigour.
It doesn't seem unlikely that a deity worshiped in Zer might have
been called Hud, making thinkable a Baal-Zer-Hud cf Balder-Hod
Anders