Nope......he should be charged with negligent homicide at LEAST!!! This is my opinion as a gun rights advocate and Texan!
Nope, NO DUTY TK RETREAT! He warned the guy to get off his property and instead of complying, the guy got up in the homeowner’s face and tried to take the guy’s gun.
I think you need to review your Texas Penal Code, then. Sections 9.41 and 9.42. He was ordered to leave, he didn’t, he assaulted the homeowner instead, he found out why when a Texas homeowner orders you to leave, you do.