## Maybe he didn't. Gus would know that whatever DEA agent he set the Salamancas on would have a fair chance of getting killed in the confrontation. Hank was the only DEA agent Gus would have a reason to want dead, or at least see some advantage in getting him killed: he was the DEA brother in law of his new meth cook. He could have easily decided to tell the Salamanca brothers that Hank killed Tuco as a way of getting the Salamancas and, potentially, Hank out of the way. That Hank actually *was* the guy who killed Tuco... happy coincidence. Yes, Gus did warn Hank at the last second, but that was just to make the killing messy and create the chance that one or more of the Salamancas also might die. Had they killed Hank clean and got away with no witnesses, they may have stuck around Albuquerque.