Cooperplace, you may be right.
At the time, the Rear Admiral and Captain of the Italian Navy who were our client reps were in no doubt that the aircraft had been shot down. They knew that the suspect navy had been trying to engage the Libyan MiG which we later learned had crashed unseen on Italian territory.
The official theory, for public consumption was, as usual, a conspiracy theory of a bomb. That's quite normal in these cases. It exonerates almost everybody in positions of public responsibility and it stops the public from thinking.
I don't know the true story behind the downing of that Itavia jet, but I entirely understand why the USN made the radar record of the salient time 'disappear'. Out of sight, out of mind. You don't need to know. It never happened. Move along. Nothing to see here. Do not discuss, especially publicly. Wait until you are officially told what to think. Most especially, wait until you are told what you can say about what happened.