In
Farhampton, it is shown that while Ted is waiting for the train back to the city at the Farhampton train station, after Barney and Robin's wedding, the mother also comes there, holding up her yellow umbrella in the rain. Craig Thomas confirmed in an interview that this is the place where Ted and the mother finally meet.
http://www.seattlepi.com/entertainment/tv/tvguide/article/How-I-Met-Your-Mother-Boss-on-Premiere-s-Big-3891090.php
No more trickery apparently. They ought to introduce her this finale.