They absolutely should stay dead- although speaking as a necromancer- it wasn't necromancy. More like a powerful illusion, based on one person's memories of the town.

[A person who might not have been literate, given how all of the written material had been impossible to read. But it would have explained why the man's family had seemed so much more lifelike than the rest of the town- his memory and sense of them were much stronger.]

Given how they died, there weren't any spirits to call back- pulsefire destroys living things entirely, body and spirit.