No, the sat doesn’t have an accurate distance to the aircraft.
It's highly likely the satellite can measure the ping delay to the nearest microsecond. That would translate to about two city blocks. Not GPS quality, but more than good enough to aid this investigation. Remember, it's through a vacuum (mostly). And there are no routers in between.
So then you are saying that Boeing and Inmarsat are lying to us and the 14 nations searching the seas off of Australia???
Is that what you are saying???