And I will add the Costco employee needs to be charged with accessory for supplying a false story.
We don't know that he did. All accounts seem to agree that he reported a man damaging property in the store and that the man was armed. Neither of those is necessarily inaccurate. Nothing in that justified an overreaction by the police officers.
If you're looking to let the cops off the hook then why not also charge the victim for not acting fast enough to keep from getting shot?