Here's what I have learned from my Vasquez cousin Bill Williamson who has done a tremendous amount of research on the Vasquez family.
Tiburcio Vasquez was one of several aliases that he used. His real name was Leonicio Cantua Vasquez b: 04-07-1835 in Mission San Carlos Borromeo, Alta CA. He also used the alias of RICARDO CANTUA. Maria Northrup in Volume II of Spanish and Mexican families of Early CA correctly list's his parents as Jose Hermenegldo Vasquez and Maria Guadalupe Cantua.
Record search for a Tiburcio Vasquez born in 1835 in Early California Population Project at the Huntington Library found no such person existed.
The true identity of Tiburcio Vasquez as Leonicio Cantua Vasquez is a known fact amount Vasquez relatives. My relationship would be first cousin, 4th removed.