Pretty Little Liar TV show fans: Question about the last episode?

Spoilers if you aren't caught up yet...

At some point, Garett and Jenna mentioned the "Jason" thing. Just to
clarify, is Jason Allison's older brother that we met in the beginning
of season 1? If so, then things would be even sketchier than before;
to me, it seems that he could have taken those videos of the girls
that they found in Allison's lunch box...