One thing that this volume indicated is that Omelas & Charlie won’t see eye to eye. We do learn that Omelas was a failed experiment, unlike Charlie. Though it is clear why Omelas hates humans, essentially his existence for so long is a curse. It is less that Rivera made him this way, but he guided him. Charlie does mention to him that he should live and not kill. Sadly that won’t get through to Omelas.
Now that we have confirmation that Charlie is in fact Omelas’s brother, the question is, how did he come to be? As Eva never gave birth to Omelas. As a surrogate mother is the only reason to explain Omelas being alive. Still, it is clear that Dr. Yuan was working close to Dr. Grossman. Could it be possible that the woman who gave birth to Omelas was not a chimpanzee like Eva, but Dr. Yuan? It would at least explain how she is both invested in and aware of Omelas.
Lucy is a character who is still finding her place. For once her mother is keeping what she wants in line. Granted she means well, but the whole situation they are in is dangerous. It is better to trust some of the adults on her than risk her being foolish enough to go behind her mom’s back. Her relationship with Charlie deepens, which was a surprise to me. Of course Charlie isn’t 100% human and would have doubts, but Phil’s wife is right that it matters what she wants. Of course the point is Charlie is still part human. If you will be associated with Charlie, you can’t have doubts like this at that point from Lucy’s angle.
Rivera’s goals more exist in pushing humanity to understand the truth about evolution and many things. It is clear that Omelas is a big use for him to use, and much like him, he recruits and uses many humans. I can guess that they will meet up with Charlie in New York.