Although clearing the Dusk Territory is considered nonsense, the Unified Imperial Dynasty in this world is indeed a colossal entity.
Moreover, this dynasty is in an extremely strong phase, and they indeed have the qualifications to make such statements. Of course, they'll understand the uniqueness of the Dusk Territory after they hit their heads and bleed.
The Boundary Breakers are now using the local forces to completely seal their exit routes, steady as can be.
The situation with the Dusk mercenaries is that those who returned cannot get out, and those who haven't returned cannot get in.
"Are all the returned Dusk mercenaries here?"
"Counting the losses, at least nearly two hundred are still outside," confirmed another Dusk mercenary. The environment of this world is very high, so there are quite a few Dusk mercenaries here.