Here's what I think happened:

Whoever they paid to put this together made this one as a joke, so when Microsoft said 'What the hell is this crap?' they could say it was a joke and hand them the real one which they had with them the whole time...

Except Microsoft never said anything, so they just kinda had to keep their mouth shut and sneak away.

Though - you do have to appreciate their actual use of the 'enthusiastic jump into the air and freeze frame' (00:58)