Heat nitpick: How did Waingro find Trejo??

So, if I'm correct, Waingro goes to Van Zant to get back at Neal, then goes to Trejo's to presumably get info on their next score by threatening to kill his wife/GF, and gets Trejo to skip out on the job, then kills his wife/gf. Bit if Trejo bails on the job as driver, he jeopardizes the crew even being at the bank job for the cops to catch them........plus, how did Waingro know where the hell Trejo was. Did they ever even speak??

Waingro only worked the one job with Neal's crew and then was ousted. He only met Michael, and they barely interacted. He was probably put on the score through a contact.

So how did Waingro know where a Trejo lived so he could give the info to Henry Rollins who, in turn, informed the LAPD of the bank job??