Anyone hit by a fucking bullet should count, and "casualties" means both the dead and the injured. Whether the bullet kills you or not is basically luck, depending on how it entered / exited (if it exited), how quickly you're given needed medical care, etc...
Because that would further muddy the waters. And casualties means deaths in virtually every other context so changing it for this one specific context would be fucking stupid.
1a : a military person lost through death, wounds, injury, sickness, internment, or capture or through being missing in action The army sustained heavy casualties.
b : a person or thing injured, lost, or destroyed : victim the ex-senator was a casualty of the last election
2 : serious or fatal accident : disaster losses from fire, storm, or other casualty J. S. Seidman
3 archaic : chance, fortune losses that befall them by mere casualty Sir Walter Raleigh
1. Military. a. a member of the armed forces lost to service through death, wounds, sickness, capture, or because his or her whereabouts or condition cannot be determined. b. casualties,loss in numerical strength through any cause, as death, wounds, sickness, capture, or desertion. 2. one who is injured or killed in an accident: There were no casualties in the traffic accident. 3. any person, group, thing, etc., that is harmed or destroyed as a result of some act or event: Their house was a casualty of the fire. 4. a serious accident, especially one involving bodily injury or death.
1. A person killed or injured in a war or accident. 1.1. A person or thing badly affected by an event or situation. 1.2 British The department of a hospital providing immediate treatment for emergency cases. he went to casualty to have a cut stitched 1.3 (chiefly in insurance) an accident or disaster.