In Item #12, SOI5 (source of information) says that on 3/11/2006 an Iraqi approached him and told him the house had been burned. The Iraqi said four were dead and one had been raped. An HOUR later, Iraqi army personnel and four US soldiers, including SOI5, went to the scene and presumably took the photos.
How did the Iraqi know that she had been raped if her body was burned?
No idea. Maybe he watches CSI.
There are more disturbing elements in the rumors circulating in Iraq - that there was hair and clothing and buttons left in the dead girl's hands. That, if true, might explain why the SOI5 knew the girl had been raped.