Some speculation about further plot.
Maybe cultists will try to corrupt the atmospheric processor? It would be a safe bet if they were Nurgle worshippers. Still, it's possible that they will try to make it spew some weird substances.
Also, it's likely that they have off world backers, and those backers will make an appearance. They are more competent with technology than some schmucks on feudal planet should be, after all. Also, there was foreshadowing about local PDF's lack of heavy weapons. And those fancy guns that she found in the hive are literally the Chekhov's guns. Sisters of Battle will NEED them.
Though I doubt that Chaos Space Marines will appear in notable numbers, unless her origin story is "Miraculously survived destruction of her homeworld and went on a quest of vengeance and justice".