Reading comprehension really can take folks a long way. Per Brandon Miller's attorney statement (easily found on the internet):
"Before Brandon arrived to pick up Mr. Miles, Mr. Miles and the individual with Mrs. Harris apparently exchanged words. Without Brandon knowing any of this context, and as Brandon was already on the way to pick up Mr. Miles, Mr. Miles texted Brandon and asked him to bring him his firearm. Brandon subsequently arrived at the scene to pick up Mr. Miles. Brandon never got out of his vehicle or interacted with anyone in Mrs. Harris' party. He was never involved in a verbal altercation with Cedric Johnson or Mr. Davis. Brandon never touched the gun, was not involved in the exchange to Mr. Davis in any way, and never knew that illegal activity involving the gun would occur."
So, NOTHING happened during Miller's interaction with Miles to reflect any form of conflict or much worse, any murderous intent to keep Miller from thinking that there was anything nefarious at hand. Only the simple act of picking up his teammate, who would recover his firearm on his own was the presented context at meeting up with Miles. PERIOD.