He survived the Jem'Hadar attack on the planet because he and another technician, Arani, had gone to a northern weather station to gather data on a covert project to edit the planet's climate without the knowledge of its human inhabitants.
He overheard the slaughter of the Cardassians by the Jem'Hadar over the radio, but his colleague Arani did not believe him, being convinced the Jem'Hadar were only killing humans. They stayed at the northern weather station for a few days before taking a flyer down to Kovalet. Their flyer was shot down by human colonists, as they approached Manea after the Jem'Hadar had left. Leterik was killed while walking in search of shelter with Arani. (DS9 novel: The Never-Ending Sacrifice)