jimjim
The flir image would not have given good depth-perception or rate of closure... unlikely that the rear crew realised how close it was either to begin with. Only ten seconds later it was apparant that things were not good.
If they had been wearing NVG, they would have seen the big rock ahead, it should have appeared on the radar picture and the GPWS would have warned them if they had been going faster - lots of holes in the cheese.