Given the equipment the crew had at their disposal and the configuration of the shuttle on this mission how could they have inspected the wing?
Teathers would have allowed them access to the bay, something else he admitted. The damage we are now hearing about talks about damage to the leading edge of the wing. Peering over the edge of the cargo bay, an astronaut could have likely seen the damage as desribed from the photo.
It seems to me that NASAs can't do attitude screwed this pooch from day one. No photos were requested, couldn't help. No EVA was requested, couldn't possibly see any damage.