Was there ever a radar track of the aircraft
KTM APP has an old radar ( gift of the Japanese after a aerie of accidents some 20 years ago. However the controllers were/still are not trained to use it (due lack resources of the Nepalese CAA) so they use it only for information to locate position of aircraft.
This is one of the reasons all domestic traffic is VFR only , regardless of type used, and you will never receive a vector from them.
We tried to upgrade the situation a few years ago but failed. Nepal is still one of poorest countries on earth, hit by natural disasters and political struggles.
Bangladesh is not much better.
Welcome to the real world.