This is quite odd. I'm unable to find any other source for the video. I've searched through the usual places such as GT websites, accounts, and the playstation accounts.
Although MotoGamesTV is a very trustworthy source of videos and usually posts videos after they are publicly uploaded elsewhere, along with its own content.
I'm going to hold my own horses right now until the trailer appears publicly from a GT Source, as it may be that MotoGamesTV have accessed a now-deleted video (that's an educated guess).