Re: Yeah...
Why would the FBI lie about this?
North Korea is absolutely loving this. Even if they didn't do it, they'd want people to think they did. It makes them look relevant and powerful, especially given the initial spineless cave in over showing the film.
What reason would the FBI have to hand a propaganda coup like this to North Korea on a plate? Unless they are pretty damn sure they did do it, and would prefer to at least control the story.