Unless the last name is exceptionally rare I fail to see why it is important.
I share a name with a guy who robbed a jewelry store. He’s no relation.
Aispuro is rather rare.
Basque origin. Found mostly in Mexico but there are 2000+ in America.
I found no info about any sibling of Emma Colonel Aispuro. Her father was in the cartel with Guzman. Aispuro is her mother’s surname. So could be an uncle or cousin on her mother’s side.
I don’t know that the conjectured relationship with El Chapo’s girlfriend is even that important to the theory that this guy might have been setup to be a fall guy.