Forget conspiracies, look at reality.
Ops Centers for airlines, ac manufacturers, and of course governments, monitor ac systems real-time or near real time.
Currently, due to security issues, public outcry, other issues, it is not generally known the level of surveillience on virtually all ac.
From the automated FDR broadcasts, to sats, wifi, and of course, the mobile devices of the passengers, it is out there.
In my opinion, the exact reasons and location all already known by these methods.
Much like AF 447, the search went on for a very long time and was then abandoned. Yet, a contractor was able to virtually go directly to the site a few years later?
I think this is much the same. With methods currently available by National Security Agencies, the location and uotcome is already known. Therefore, it is not in their best interests to reveal the information and associated levels of surviellience.
There is no need to rush, the outcome is the same, if the search takes 5 days or 500 days..and therefore, no need to compromise security.