Thanks for putting this back on here. I pondered it several times before the computer monster got us. I did a little scouting around but didn't turn up much. The name Hyam is a lot more common than one word think at first.
"What our ancestors would really be thinking, if they were alive today, is: "Why is it so dark in here?"" From Pyramids by Sir Terry Pratchett, a British National Treasure.
Looks like a great suspect on paper, lots of circumstansial evidence and is a very interesting proposition. The only thing that would rule him out for me is his appearence. He certainly doesn't look like someone who blends in very well. In fact he looks rather scary.