2004 vintage would have the floating firing pin, as opposed to the one mounted directly on the hammer. In my experience, these are more likely to have FTF if the mainspring is messed with, or the strain screw is backed out. This might be the fault of a shadetree armorer in pursuit of a lighter DA pull.
This vintage would also have the much reviled internal lock.
The barrel issue looks like QC to me.
I trust they ruled out an ammo issue. Do you have a link to the S&W forum? Sounds like a good place to browse.
I wonder if the Colt King Cobra also has this. I've got one that won't open.