There were a lot of De Meza families in Spain, one was awarded a title for fighting the Moors at the time of El Cid. There is a Casa De Meza in Tolado old town. There was more than one De Meza mentioned in text about the Conquistadores. It is thought that Morano Jews fled through Portugal, some jews were known to take on Spanish names to escape the inquistion. We have not traced the Dutch Demeza's from before they entered Holland.
There were De Meza's in 1600's San Francisco probably from Spanish rich families. Some of these went into Mexico.