If NPCs want to occupy another territory, the appearance of those monsters has undoubtedly indicated that their plans could already be dismissed. After all, what these NPCs are facing now is a King Level Monster. And given the strength of a King Level Monster, although it might not be possible to confront them directly, they also weren't without the strength to fight them.
However, these NPCs didn't even understand where they were. Even if they managed to defeat this King Level Monster, it didn't mean new enemies wouldn't emerge at that time.
Considering the NPCs' idea of occupying new territories, it could be said that the NPCs' actions had already failed before they had truly begun. If those NPCs continued with that purpose in mind and were extremely cautious, then they could have chosen to withdraw right away.
