I will answer that, sir, but I do not have all the details. You are asking a very specific question.
The example you used was of a leg injury sustained in Kandahar. In all honesty, I cannot imagine that there can even be any confusion about a case like that. As you just said, the CF 98 form is a document that soldiers fill out with the assistance of their chains of command; it allows the event to be linked to the date and place where it took place. Even the chain of command indicates on the document whether, in its view, the injury is service-related. The commander signs the document, not the medical support chain. That allows the doctors to do their jobs. We are talking about the same event. There is no secret as to the location and time when events took place, but that is of no concern to the doctors.
However, other documents are given to veterans, specifically the CF 98 form that you just mentioned and the medical report containing the doctor's diagnosis. Those are the documents that say that it is clear, for example, that a soldier will never walk again, and that he is entitled to certain benefits.