I can understand why you are confused.
"Casualty" means that someone has been killed or injured. The term "casualty" is usually used in war and law enforcement (police). However, it can also be used FIGURATIVELY to mean being a victim of a tragedy or terrible event.
For example, "The lost jobs were casualties of the economic downturn." They were not literally killed, but they were victims in the sense of being eliminated.
"Victim" does NOT necessarily imply injury or death. "Robbery victim" simply means that a person was the one harmed, targeted. If there is no other information, there is no reason to believe that the victim was physically hurt.
In other words, casualties are physically injured victims of something (war, disaster). But not all victims are casualties - they may be tricked, robbed, etc. but not necessarily physically hurt.