This whole thing stinks to me. Are you sure the gun was working just fine before he shipped it out? Its easy to ship a broken gun and "claim" that its CP's fault. For instance, if the gun was nicely packaged and secure when shipped and it still broke. That raises some flags. If the gun was poorly packaged and broke well then thats the sellers fault.
Another question. Did you actually see these emails sent to this guy? Or it this all second hand information. Ie did he forward you the emails he received.