Basically, that video are the clips of the 'ghost' that was recorded while he was playing the game. Kind of his way of showing proof. The strange, clone Link is supposed to be the spirit of this 'BEN' person that the file was named after. He bought a Majora's Mask copy from some old man and it still had a file saved on it. He tried to delete the file, but it came back and strangeness ensued.
As far as I know, no one has been able to reproduce the things that were recorded from that 'haunted' game. If someone has, please feel free to correct me on that.