This is also why, in the late decline of the Goblin Empire, the goblins chose to perform "full-scale loyalty" by reducing the intelligence of all their kin to idiocy through special means.
As long as there is nothing in the brains of my kin, no matter how much you want to extract, you won't be able to get anything.
It was precisely because he realized this that Kael would later choose to stand with the goblins without hesitation.
As for how Kael came to this conclusion...
This involves the third piece of intelligence.
First, with the strength of the multinational Alliance, the battle unit led by Kael that launched the attack would be annihilated, and the fleeing goblins could not hide and would become playthings in the hands of the Chosen, making it unreasonable to deploy only one Chosen in the frontline of the army.
So, when he saw that his enemies had but one Chosen, he realized the problem.