Wow! You guys have been busy! I am just now being able to catch up from having company over the Holidays!
First of all, even when Detectives were at Universal with Casey, they make it abundantly clear to her that she is NOT being detained, the door is not locked and so on. That statement/conversation on tape can be used against Casey. You do not have to give the Miranda warning to anyone during the investigative phase if you are merely doing interviews to determine what has taken place.
If you will notice, Detectives are covering the bases in interviews by mentioning at the beginning that whomever they are interviewing is there willingly and of their own accord. This is on tape.
It is the same with Lee's interviews. At the very beginning, even Lee states and acknowledges that he is there of his own accord and speaking freely. This can be used. If Lee lies during the interview, it will become a problem for him later on in the investigation.
I do not see Cindy and George setting themselves up to take the 5th at trial because if their testimony would tend to incriminate them, then they are implying to the jury that they know more than they are willing to admit and knew that their actions were wrong. Their lawyer is asking for immunity for them, IIRC, because some of their statements and actions are chargable. I am not a lawyer, but I do know from LE point of view that if the Anthony's are trying to derail the investigation, lying about important events, destroying evidence (whether intentional or not), they are setting themselves up for Obstruction charges. LE or the FBI can decide whether or not to charge them. And we all know that you just do not lie to the FBI or try to derail their investigation.
LE and the FBI know what they are doing, IMO, and I believe in them. I think they know how to interview so as to get the interviews into trial. This post is in regard to the speculation that so many of the interviews not being allowed in at trail. I think the interviews will be asmissable because the bases were covered at the beginning of the interviews.
Just JMO, as always!