At the 12:32 point, the runner was NOT out at 2nd. The show of brilliance was on the part of the first baseman - to not assume the double play happened, and continue playing on the runner going home. The runner going home turned out to be the third out.
@@Jivvi (I'm not sure on this) - I think that the ump at 2nd did not make a call, which means the runner was not forced out. In a tag play, he would have to signal either safe or out. I think the first baseman realized this - and wisely threw home to get the third out.
0:47 This is a terrible ump call. Not because of an infield fly or intentional drop rule, because those rules do not apply here. The bad call is that there was only one out made and not two. When the first base man throws the ball to the second base man covering first, he's touching the bag. That's a force out on the batter. The runner on first can stay on first without being tagged out. The runner on first was then forcefully pushed off the base. It wasn't much force, but by rule that's obstruction on the second base man.