From known facts, the transponder was turned off, no radio comms received, and no crash in the area. This implies interference.
The one garbled transmission could have been sent during a struggle.
Its not guaranteed that this aircraft has crashed, or that any hijack went wrong.
What if the miscreants wanted an intact 777? They would have a suitably long and remote field prepared.
The cellphones ringing angle is interesting. Is it normal for a ringtone to be received upon calling a destroyed cellphone? It would be enlightening to know through which base station the calls were routed ... Last point of departure or somewhere else?
I wonder if Li Chi had anything to do with this?