The visitors struck first, stunning the home crowd inside the first minute when Andres Romero cut inside the box and found the bottom corner.
Toronto took the lead with just over 20 minutes on the clock after former Birmingham City defender Steven Caldwell headed home Brockie's cross.
The second half was a different story as Toronto squandered several opportunities to further extend their lead before Montreal pulled a goal back.
Camara hit the back of the net in the 69th minute to reduce the deficit, setting the stage for a dramatic fightback.
Veteran Italian striker Di Vaio completed the comeback moments after play had restarted, latching on to a through ball from Felipe Martins and placing his shot into the centre of goal.