If we take Misty's statement seriously, the one they don't care about is cousing Joe. There is no indication at this point that RC is in involved in Haleigh's murder, other than as a grieving parent and thus a victim of violent crime.
Certainly, until LE states that the case is wrapped up and those responsible are tried or accept plea bargains, it is possible that RC's status in the case could change. But right now, it is hard to imagine that Tommy's attorney would be out there selling a story that his client, his client's sister and their cousin were the ones involved if indeed it was Ronald.
RC is in jail and will be for some time, because of the drug charges. If LE thought he was Haleigh's killer, this case would have been solved months ago. All of the charts have indicated that the birth parents are not involved and so far that appears to be holding up.