Chavez (correctely spelled Chávez) is not pronounced shu-VEZ or chu-VEZ, but CHAH-bes in American Spanish or CHAH-beth in Castilian Spanish.
Madrona is not pronounced mah-DROHN-uh, but mah-DROH-nah.
Zamora is not pronounced zuh-MOR-uh, but thah-MOH-rah in Castilian Spanish or sah-MOH-rah in American Spanish.
The CH has always the sound CH (as in church). The pronunciation with SH correspond to French, not to Spanish. The Z has a sound S in America Spanish and TH in Castilian Spanish. The V and the B have the same sound B.