The Imposter (2012), what do you think happened and does it matter?

I just watched The Imposter and I'm trying to tackle the subject matter. On one hand, I'm riveted by this story and want to believe there's truth somewhere in the ring of lies. But after finishing the movie I can't help but think that I doesn't matter. Nicholas Barclay is long dead and if his half-brother had any thing to do with it we'll never know. At the same time, it's that la-di-da attitude which got the story to this point.

So, what do you think happened to Nicholas all those years ago and does it still matter in the sea of missing persons reports?