A truce assumes honor amongst both sides in a disagreement, not honor of criminal action. Once the kidnapped victim gave testimony of others still being held captive, those receiving the report were duty bound to act upon it, not to honor the criminal behavior of their adversaries.
With over 500 different tribes/nations of ‘native Americans’ throughout the continent, I haven’t found much in common between them other than perhaps most were pagan. It isn’t surprising for those who worship demons to also oppose anything Christian, even degenerating into cannibalism, but the relationships with settlers and colonials with Native Americans is as diverse as European History. Freedom and Liberty tended to follow the path of Christianity than any other substitute for a relationship with God.
You are quite correct that tribes varied greatly.
As an example, it appears rape was surprisingly rare for captives of the Iroquois, but routine and appalling by the Comanche.