I think the issue with phone records will be that they most likely used prepaid phones. Because who are we kidding...they didn't sign a contract with a carrier. Therefore, say you owned phone A at the time of the murders. Well, 10 months has passed, and you no longer have that phone. Prepaid phones are a dime a dozen and free with 1-3 months prepaid service usually. So as far as LE is concerned, DN and KN will never disclose the old phone numbers or prepaid lines they had. Those are long gone, and totally un-traceable unless LE has some inkling of the names of the accounts and which carriers they went through at Walmart or wherever their ridiculous phones came from.
I could go buy a prepaid phone today, use the name Sam Smith, then throw it away when I'm done with it or stop paying the bill (which judging by the Nations list of civil cases is the most likely scenario). When that happens, if LE came to question me about a crime that I was implicated in, I'm never going to tell them about my Sam Smith phone. And they'll never know, unless they subpoena every carrier out there and search for my name or addresses. Assuming I used my real name, which I wouldn't if I were of the Nations lifestyle and running from 10000 court cases. Again, who are we kidding...there are so many prepaid carriers. There are a million names and addresses they could have used. There are a million reasons why the carriers don't have to send those records with such a broad sweep. You have to have more than this to get a subpoena.
So it's just another "cannot include or exclude."