Susan- I have a similar situation in my family involving quarreling realtives which ended in one family member changing their name from "MEYER" to "MEIER".
Our family in in the Greater Cincinnati/Northern Kentucky area. I recently contacted a relative ( unknown to us until now ) that I found with the "MEIER" spelling.
As far as the dropping of the "L", sounds like somebody just wanted to change the spelling. "Ziegel" means brick. I don't know if "Ziege" has a unique meeting. There is a post to this group from a "Ziegenmeyer", "Ziegen" meaning goat.