You forgot the Deus Ex Machina explanation at the end that made literally everything before it a non sequitur.
And he had no new ideas. Anyone that reads that series and extolls the originality of the Dark Forest theory hasn't read any science fiction to speak of, let along Saberhagen's Berserker series from the better part of a century earlier. He had nothing new, he was a literature prof writing his first SF book and doing it way worse than any literature prof should ever be at writing.
Fucking garbage, I was angry and upset that I had wasted time reading that shit and wanted my money back. If anyone tells you that was great SF, you can safely turn your back and walk away, they have nothing useful to contribute to a conversation on the matter.