However, nothing, so far, indicates that the plane has crashed. If the plane has actually managed, ON PURPOSE, to avoid radar detection, it could have as well landed in secret somewhere else.
True, but the only theories under which this would be a logical course of action are fucking stupid. Someone did this to steal a 777 to use in a 9/11-style attack? There are lots of ways to get a 777 that would be WAY easier, such as: leasing one.