First of all welcome to the forums.
Kalani did mishandle the situation in so many ways. If he had told
the Tower folks about what had happened to him in the first place they most likely would have helped him. But he has also just met these people and had no idea what they were like.
As far as some of things you brought up specifically: It seems like Kalani bailed on being the rat because he got freaked out after the war. Think about what it would be like to look around after the battle and see what
the Mallers were capable of doing and then realize that you are the one responsible for causing it. He didn't want to help these people out anymore. He only helped them in the first place because he thought he had to to protect his daughter. After the war his priority shifted to laying low and trying to find another way to get
Hannah back that didn't involve causing another situation like the war. At least that's how I see it anyway.
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