What did Kenny Schrader see?

Seeing Dale Jr. drive the #3 reminded me of a question ive had for years now. If you have seen Dale's fatal wreck, you may have noticed that Schrader was the first person on the scene of the wreck (him being involved and all). He took one look in the car and began frantically waving for EMT's. Ive read interviews with him saying that he will always be haunted by what he saw. SO, out of morbid curiousity, does anyone have any information on what exactly he saw. Based on the injuries he reportedly recieved i wouldnt think any of them would be overtly visible.