On the topic of what the families have been told and why, I would refer to this conversation between MP and DC in episode 9 of Down the Hill. When MP talks about doing what DC has asked him to do, I think he is referring, at least in part, to staying patient about not knowing certain facts about the crime at this point in time:
MP: We’ve met and we’ve talked a lot, and corresponded back and forth, and we’ve been from one side of the country to the other [Carter interjects “literally”] and we’ve actually become friends. And that’s a good friendship, I do like that and I cherish it. But you’re right. You owe me. You owe me something. [Carter: “Yep.”] But I’m going to work as hard as I can to help you deliver on that, and you know that, and I’ve maintained that position, and I won’t change that position, because we are working to the same goal. I’m not going to stop. Anything that Doug has asked of me, I’ve delivered, or done my best to deliver, and I’ve asked something of him, and he’s working as hard as he can, and his team and supporting it, to make that delivery and one day we will. It’s just a matter of time….Trust me, I want this thing solved yesterday, as bad as anybody, probably more so. But I realize that it takes time. Because there’s really two deliverables here. One is, Doug and his team building up, making a case to make an arrest. Then it goes over the prosecutor, who has to prosecute the case. And we can’t lose sight of that because we’ve got to get it right...
DC: Once the arrest is made, all 50,000 tips are going to be dissected. Every single one of those tips will be dissected, and we’re going to find out if there's any kind of activity. Because if we jeopardize this, we can’t pull it back. It’s easy for the media, or citizens, to say “I think it’s this” and if they’re wrong, it's okay. But if we jeopardize this, we own it.
MP: And I’ll hold people accountable. And that’s why we’re going to get it right. It’s a tough row to hoe, but I entrust in what LE’s doing. So when they call me. Doug will call me - and say, “Mike, we got it.”