There are two documentaries by the director about the making of this film and aftermath of the earthquake. He does find that the two lead boys, played by the Amapour (or Ahmed Poor) brothers, survived the earthquake.
Babek Ahmed poor who starred as Ahmed apparently did not die in the 1990 earthquake as Robert Osborne said. He made movies afterwards. Not sure about Mohamed Reda Nematzadeh. He may also still be alive. Per the TCM showing of " The Story of Film: An Odyssey"
According to TCM host Robert Osborne, in 1990, 3 years after this film was made, a devastating earthquake destroyed the village where the story takes place. Thousands were killed, including the two boys who star in this film.