> Was he being serious or just trying to score some sympathy of Jews and Christians?

He's just ignorant. Jews would not vote for someone who knows so little about their history. Christians may not be as familiar with the history.

According to Jewish history Josef stored grain in the year 1532BCE, but the pyramids were mostly finished by 1759BCE, more than 200 years earlier.

The pyramids having anything whatsoever to do with the Exodus is a myth created by Hollywood, it is not a Jewish belief at all.