Since Zhou Tian had no intention of directly confronting those goblins, his plan was to gradually erode their power in a 'boiling frog' method. He believed that once most of the goblins chose to flee and accept his rule, any hidden trump cards of the goblins would no longer have any opportunity to shine.
Although the goblins' character weakness was glaringly obvious, and Zhou Tian could easily achieve his objective by exploiting their weakness, these goblins were not stupid, especially the goblin leaders who, being out of the frontline, could keep their cool. If Zhou Tian didn't have other tactics, even if he could achieve his desired result, it would take a long time before the goblins were scared off.
Looking at the situation, Zhou Tian had to let these goblins realize that fleeing was the only right action when facing him.