Very early in the investigation. Always possible that new evidence will emerge to assist a justification defense. That will be a steep hill given that video footage.
Not sure a judge will even give a self defense instruction on all three shooting decisions by the lad. There has to be a factual basis.
If the case goes to trial, voir dire will be critical. Prosecutors will seek hard cold fact finders.
Defense counsel will seek jurors like you and Tampa, who endorse the shooting of unarmed people who had the gall to either confront or attempt to apprehend Kyle, but never presented the type of imminent threat that would justify the use of deadly force.
In other words, if an aggressive drunk asshole is trying to start a fight with you at a tailgate, it is unlawful to shoot him dead with your AR-15. I provide you with this advice as it does not appear you understand when deadly force is permitted.