Thanks for responding guys - I've been in a training session all week and too braindead to log in at night.
If it isn't a transcription error (would the RST have picked it up and requested it be fixed?), then I guess there are a few possibilities. The first that springs to mind is the Stines. If memory serves, they were the only ones not called over that morning, although they seemed to be very close to the Rs after the event. However, presumably the touch DNA has been compared with samples from them.
The other thought is something that someone mentioned on here ages ago (apologies - I can't recall who). JRs company was part of the Lockheed group. I would just about guarantee that they would have procedures in place for their executives who may be targeted for kidnapping, blackmail etc. JRs first call should have been to activate those procedures. What if he did? What if Lockheed sent someone over to help "clean things up"? I can see holes in this of course as well, however someone somehow managed to get a message sent that morning to treat the Rs as victims, not suspects, and managed to get the telephone records wiped.
Just some thoughts from a brain somewhat frazzled.
You may be frazzled, but this exact idea has been suggested before. I am sure Lockheed had a protocol for just this kind of thing- we'll never know how much outside help the Rs had that night. Because of the timely and very suspicious absence of phone records for that night, it has to be assumed there were calls made from and to the R home that night that would be suspicious.