No they didn't. He cut in front of the pickup and began attacking the guy with the shotgun trying to grab it from him. At that point its kill or be killed. The guy legally had the shotgun, having the gun did not justify Arbury attacking him. PERIOD. They also have video evidence of him going into that house and looking around. One would assume that it was to steal something, he just didn't find anything worth stealing. The neighbor across the street yelled at him to get away from the house and he took off running. That's when he was chased. Burglary is a felony which means the McMichaels had a right to detain him. You do not have to steal something for it to be burglary, just entering the property with the intent to steal is enough. He had zero business in that house and there is clear video of him walking in and looking around. Was he trying to find his missing baseball? Hell no, he was looking for something to steal. Once he began attacking now he's a dangerous criminal and they think he's committed a felony and is trying to take someone's gun. Shoot him quickly to end the threat. They did what they had to do. When even a black dude agrees with me, you know you're on the losing end. Dude had a rap sheet and run ins with the cops before.
Don't make up shit to try to fit your narrative. Look at the facts of the case.