My theory is that the network said to the family, "You have to use this guy. He's a PI. He's worked with other families. He'll find your daughter. Blah Blah Blah" and the family said "Ok" because the media comes across as being very powerful, very big, very intimidating, and they feel they can't say no to them. I'm sure they found some BS way to 'sell' this guy to the family; either by saying that he'll find Lisa or that he can be their connection to the media to keep Lisa's face in the spotlight.
Also, if the network did play a part in bringing this guy into the case, doesn't it seem like they are purposely creating a media circus? In other cases, it seemed like crazy stuff just happened on its own. I'm pretty sure no media hired Cobra or Leonard Padilla.
In my first post on this thread, I mentioned how John and Patsy Ramsey hired PI's too. I'm really starting to see a difference between how the wealthy handle something like this and how everyone else handles it. Lisa's family's PI was supposedly paid for by the media, and they have a sensational, sinister purpose to do something like that. The Ramseys had money, so the were able to hire their own PI's and didn't have any reason to fall for that BS by the media. The PI's in the Ramsey case also come across as being very professional and credible, and when people watch them on TV, it's hard not to think that the Ramseys weren't involved. But when this PI goes on TV and is 'speaking' for Lisa's family, people will probably start to think that the family is involved, that they're crazy like the Anthonys, love publicity, etc.