So now we know there is a confession from Casey that she threw Caylee's body into a dumpster. That is evidence. The prosecution will probably subpoena the female BH. A confidentiality agreement, a private agreement, is not going to prevent that testimony from happening. The prosecution may not be able to get to that information if they try an interview, without a subpoena, but they will be able to get it. A private contract cannot prevent the government from performing their prosecution function or prevent the judges from allowing the information to come in and ordering the witness to answer truthfully. Even an act that is a communicative act -- like nodding a head up and down is understood to mean yes. It is treated the same as a verbal response. The female bounty hunter communicated in a verbal act that Casey somehow communicated to her that Casey threw the dead body of Caylee into a dumpster. That's a confession from a perpetrator. The statements of Casey are admissible -- even the nonverbal statements.