I understand how you would see it that way, however, that is not what their statement means. What the meaning of that statement is trying to say is that there can be a history that doesn't include physical or severe abuse, but could still pose a "threat" to a person or child that can create complex PTSD too. For example being bullied by another sibling or by other children is enough to create enough "stress" for a child to where that child or an adult can develop what they are calling "complex PTSD". They have broadened the circumstances in which the person can endure "stress and a kind of captivity" to where they can develop "complex PTSD".