The NRO knows exactly where the plane went down as it has in other lost aircraft incidents, and in the case of re-entering satellite debris. Very rarely is any of that information released to civil authorities. Release can be authorized if survivors are suspected, which wouldn’t be the case here.
Depends. If they had a bird on the right orbit, overhead at the right time, looking in the right direction, with the right sensors then perhaps. Are you claiming that the NRO's assets are covering all of the Earth, all of the time? What do you think the odds are for this particular bit of the Earth's surface?