Nelix was still the ship's ambassador, and his duties in that regard would require him to be in contact with local authorities. During such conversations he would be trying to find out anything that would help Janeway, such as local hazards or areas to avoid. A planet at war would certain fall into that category.

The fact that he hadn't already briefed Janeway on it would be a good followup question. But maybe the planned course through the sector wasn't in that direction and he felt it wasn't worth including in his updates.

Neelix was still the ship's ambassador, and his duties in that regard would require him to be in contact with local authorities. During such conversations he would be trying to find out anything that would help Janeway, such as local hazards or areas to avoid. A planet at war would certain fall into that category.

The fact that he hadn't already briefed Janeway on it would be a good followup question. But maybe the planned course through the sector wasn't in that direction and he felt it wasn't worth including in his updates.