I have to start off by saying that this was by far the season's best episode.
Viewers got a little bit more background on Demetri and
Al's relationship during the elevator scene where they reminsece about the days
when Demetri would "crash" on Al's couch and play videogames together. While Al
recalls Demetri cheating during the games, Demetri jokingly responds by saying that
he simply "found a way to change the game." Those words come back to haunt him
when Al decides to end his life as a way to change the "FlashForward game," and
the fate of his coworkers.
Through his flashforward, we finally learn what Al has been (secretly) struggling with; the accidental death of a mother at his own hands. He saw suicide as a way prevent his, Demetri's and Mark's visions from happening--now Demetri can focus on Zoey and the wedding, and Mark can begin to work on his marriage. We see clips of these things beginning to take place during the montage at the end of the episode were Demetri is reading Al's letter.
My question is, was there another way he could have tried to prevent Celia's death from happening?
RIP Agent Gough, we'll miss you.