All of those posts assumed this was a bad guy and I said that repeatedly. If this guy was innocent, I'll be the first one to say bring the cops up on charges. The first one.
The only justification for use of deadly force is fear of life. Innocence of an underlying suspicion, in hindsight, is irrelevant.
This holds regardless of error in execution of a warrant.
And, homeowners have the right to use deadly force against unlawful entry, including errors in execution of warrant.
Notice the past participle. "If this guy WAS innocent." That's right, Sugarpants, because he's DEAD now and we really don't need your stinking affirmation.