Use lies to combat lies.
I still think the best way to get her to talk is to reveal that Lee or Cindy has been doing something underhanded to try and position the blame more squarely squarely on her: Whether it's true or not, it should get Caylee thinking about it. It's vague enough to be anything, from a family scheme doing illegal things to protect her in this legal situation, to a family that's coercing her to lie for whatever reason, or to "hold out" for something that'll make her walk.
(Fake.. this isn't being reported, it's just a suggestion to get Casey to move)
"Lee says Cindy told him Caylee is actually dead and she's going to make an annonymous tip to those body searchers she called down so they'll find her. He says he knows more about the deal, and has known all along, but was pretending otherwise to help out Cindy. Turns out Cindy doesn't NEED help.. Cindy also told Lee that she's got everything ready to push the blame squarely onto Casey for her death, 'where it belongs and we'll be done with it' and she's ready to go live her life now.. she even called you a selfish





for putting her through all this in the first place. He says he's changed his mind on the plan because now he's thinking that despite what he knew previously, he thinks Cindy is actually the underlying cause that made all of this happen, and that he might be the target.
Lee has suggested I tell you about all this so that you can fill us in with the missing information and bring the right person to justice... He told me a little more about something else too, but I'm holding it back to ensure you're being straight with us. It's a test.. you tell us what it is, and we'll be forced to beleive everything you tell us.
Here's the thing though.. we already knew about George but we didn't have all of the pieces.. we still dont. However, Lee is pushing our hand saying that he needs you to come clean on your mom because he suspects she's actually going to turn things on him, despite what she told him. Lee says his fate is up to you.
Now come on Casey, your brother is sticking his neck out for you. We have enough to keep you here, and it looks like your mom is about ready to dump some more on you to ensure you either stay, or get the death penalty. The only way to protect yourself here is to help out Lee in going after your parents, or maybe help your mom by going after Lee.
Either way, it's not pretty, but you can see why I'm not providing you with the rest of what Lee told us. He's either lying, or being truthful, if he's being truthful you'll back up his story without even knowing it. Or.. Is he lying?"
"I don't know how we missed his involvement before this. Is HE the one schmeming this? or was it George that told you to stick to your guns regarding the date you last saw Caylee and dropped her off? PLEASE don't say it was Cindy who advised you to do that and then dropped the bomb about taking Caylee to her dad's place for Father's day.. If she IS, you're an idiot because she's she's got you lined up for the fall with that one. THe confusion is creates is only one that will point the finger straight at you and you alone. You can't do the whole "insanity" defence because it proves that you're hiding the truth, meaning you're aware of right and wrong, which makes you ineligible. Mom's a smart cookie.. looks like a set up to me.. but if there's nothing but Lee's testimony to go by, you might be in some big trouble here.."
You won't even get plausible deniability, or have a smokescreen for the jury. If what Lee says is true, there's no state in the country that's going to offer you any protection from a jury that's going to crucify you on sight. Better hope you don't get one in a state where Hanging is legal or something.
This might work because either she's in this alone and the family (minus perhaps Lee) is stupid, or perhaps she's got some kind of fabrication that she DOES beleive in that she'll want to press. Most importantly, it reminds her that she's not going to be able to plead insanity, in case that's why she held to the June 8th scenario.
Either way it appears to cut a path to the death penalty, and/or a reduced sentence with cooperation. Plus, if there truly IS some conspiracy with the parents, this could reinforce what's been discovered so far, or perhaps tear holes into it. Any info she gives.. lie or not, could shed light in areas that haven't been considered yet. If she refuses to play the game.. no harm done.
Or hey.. Why not have her come out of jail again and then stage a kidnapping/waterboarding event apparently masterminded by concerned local citizens? That'd be even easier.