Very well put.
I think both parents of Max (DS and JS) were shocked when Max's doctor, Dr. Peterson at Rady Children's Hospital told the Coronado Police Department he did not feel the visible injuries were consistent with the cardiac arrest and brain swelling experienced by Max. Dr. Peterson expressed concerns based on the above factors that suffocation may have occurred prior to Max's fall.
http://www.kpho.com/story/15527429/...ests-maxfield-shacknai-suffocated-before-fall
Below is my own opinion.
I won't be surprised if DS and JS did a background check immediately on the woman who'd been with their son after Dr Perterson voiced his opinion. It's very possible that the several things that DS often talked about (RZ's shoplifting arrest, RZ's complaining about Max to her family through her email, RZ's frequent contact with Neil) came out around that time through a private investigation. Otherwise how would DS know what RZ said about Max in her email to her family or how frequently RZ contacted Neil? JS probably knew this too as Ann's book reveals he mentioned to police that Neil and RZ talked almost on a daily basis. I don't think any man or woman would feel comfortable with their partner's daily contact with their ex. It was possible but unlikely that RZ told JS about her close contact with Neil. Another way to find out was to review RZ's phone record through a PI.
If the above records of RZ were indeed revealed through a PI around the time Dr Perterson suspected Max was suffocated, Dina would be outraged. Besides blaming RZ for being responsible for Max's injury, she'd blame JS for bringing RZ into their lives and Max's life.
What about JS? Did he believe Dr Peterson's suffocation theory? Did he discuss it with his friend Dr Luber? Did he feel betrayed when he learned about RZ's criminal history and her close contact with Neil? Did he blame her in some way or blame himself for entrusting Max with her? We don't know because he never talked about his feeling in public like Dina did.