The reason why Ultar would withdraw his men is not because Ultar chief would not want to help him.
Instead, he would be wary of the Nergui tribe.
Nergui tribe withdraw his men and said he wanted to protect their area.
That is a reasonable reason
But what if Nergui tribe uses this chance to attack Ultar tribe? Even though the possibility is small, there is always a chance
Chadha had calm them down with a big picture, taking in the circumstances of the world into account
But the human hearts are the hardest to fathom
Chada has already open up to these two tribes about what he intends to do. So, there is a big picture here.
But could Ultar be at ease? What if he did not withdraw his men and suddenly Nergui tribe attack his tribe and he would lost his home?