What the uploader of that video has done is predict a frequent event set of events, such as earthquakes and volcanos, and predicted one to occur over a 12 day period. It is absolutely assured over such an interval to have something happen. She then got 'lucky', the Japan earthquake barely fit in her interval. So it's not a terribly risky prediction for her to make.
What she isn't doing is checking the alignments of the literally hundreds of Near Earth Objects and comets, and noting when alignments occur but nothing meaningful happens on Earth. Doing so would destroy her case.
However, she will be treated as quite the seer by the 2012 community for quite some time.