While he had written a number of books about Egyptian history and geography, this article doesn't concern itself with that. They concentrate on his insistence on the fantasy that today's Ashkenazic Jews had descended from Khazars.
Apparently, he claimed to have proven that Jews who had lived in Europe were not related to the original Jews of the Bible because of the shapes of their eyes, hair color, and - especially - the shapes of their heads.
Yes, he based his theories on the pseudoscience of phrenology, which had already been discredited a century before.
But the article says:
All of these facts that Hamdan was able to prove angered Zionism, so he died under dire circumstances. It was said that his tragic death in a fire that consumed his apartment on April 17, 1993, was surrounded by many doubts on the part of his family and disciples, as they thought it came from the hand of the Israeli Mossad, which was tainted with the blood of many scholars and writers around the world who oppose Zionist ideas.
That's it. He espoused a ridiculous theory that had been popular among many for over a hundred years, and he died in a fire many years later.
That's enough to publish a conspiracy theory that the Jews killed him because they didn't want people to talk about the Khazar theory.