Probably watching CH doings on their predphones, I mean if you take a look at the novel, CH seems to have taken interest in coming to hunt on Earth specifically because of Dutch killing JH which caused some suprise back in the homeworld. Could be a resquest of him to hunt there, his birthday, maybe at one point they were gonna take turns, he was on a rite of passage, later entries refer to CH as a young blood so kid could be on a test.
CH was gonna keep hunting until he got enough I guess, how long did the events lasted? Some weeks? Whatever future plans they had planned was forgotten when CH f**ked up.