I finally had time to watch the entire Brainscratch podcast. I also just reread Knox's post #574, and if you can't take the time to watch/listen to the podcast, Knox has captured the main points. I will note a couple of things that stood out for me during the interview with Adrienne's sister, Jenny, who is very articulate. A good portion of the interview is based on "theories" that Jenny and other family members/friends have discussed based on the limited information that they've been given in the case. It doesn't seem like the family has much more information than as been presented in media reports or discussed here on Websleuths. The family has "theories" not unlike those of us following the case.
There were a couple of instances during the interview when Jenny hesitated to respond to a question posed to her, and "eye searches" were obvious before she answered. I don't know if this is significant or not. I don't want to speculate aloud and will keep my thoughts to myself for now.