How Jack and his crew could've been acquitted of shooting Hank and Gomez

After Jack and his crew killed Gomez and shot Hank in the leg, instead of killing Hank and burying their bodies, they should've called an ambulance and turned themselves in. Then they could've argued self defense. They could've said they told Hank and Gomez they'd drop their weapons if they showed them their badges, but they refused. Then they had no way of knowing they were actually cops. Anyone can say they're a cop, that's why they have badges. They could've said that since they weren't showing their badges, they had good reason to believe that they weren't actually cops, and that if they had dropped their weapons, they would've been killed. Also, Hank kinda lied. He yelled "Police", when they weren't police officers, they were federal agents. Also, they weren't really dressed like law enforcement officers. In fact, they were dressed similarly to Jack and his crew. They had good reason to believe they were hitmen and/or dealers. Hank would've confirmed all this, I don't think he would've lied in court.