Washington Post says the overdub is fake:
http://www.washingtonpost.com/blogs/...ke-in-america/
Other sources saying overdub is fake:
http://www.businessinsider.com/north...america-2013-3
http://askakorean.blogspot.ca/2013/0...deo-shows.html
But I mean we can keep debating it here without doing research, that's good too.