I don't think its blackmail when you are threatening to kill the guy @buyer
You are mistaken in the order of events. Buyer sent information to BCB to enact a transaction that BCB offered to initiate. Then BCB blackmailed buyer by threatening to expose his name and (presumably) his personal information to the internet including known criminal actors. When it became clear that BCB was threatening blackmail which he sent to me thinking I am Buyer I started a thread to call out BCB's actions.
Later on when BCB threatened that he had pictures of Buyers kids and he futher threatened to publish Buyers identity Buyer apparently, and rightly, made clear that if BCB ever came near Buyer or Buyers family (which BCB was offering to share with known other criminals) at that point Buyer made his position known that he would kill BCB if BCB came anywhere near Buyer or Buyer's family. I'm sure under state statute Buyer, who allegedly lives in Colorado, is protected in his direct statement that he would protect his family by killing BCB if BCB the known blackmailer or any of his "greasy little friends" ever came to harm the Buyer family.
That is the chain of events.
Sean you do realize you just posted as the wrong alt.