I just finished listening to part 2 of your chapter 2 discussion and I enjoyed every word. I'm really glad to hear you diving into the interplay of memory and imagination that I think is central to the book.
Thinking back to chapter 1, I'm reminded of the Indian Treaty that the grownups spend Den's fifth birthday party forging. I read this as the white settlers' willingness to paper over an ugly truth with a self-serving fiction. It's significant that Den remembers this so clearly and that he recounts it immediately before the Bobby Black incident. To me, what he's held onto is that it's okay to make up lies when it serves your purpose, even when that purpose is avoiding your pain, or your moral failings.
I suspect that Den is unconsciously prefiguring the arc of his whole life.