The "Ransom" doctrine makes no sense. Not the Witness interpretation nor mainstream Christianity's.
According to scripture he was dead for 3 days. So the "sacrifice" was giving up a long weekend. Then, if one is a trinitarian, it becomes even more nonsensical. He sacrificed himself to himself to save humanity from himself.
There may or may not have been some person in Palestine who preached the admirable things that Jesus was said to have said. But countless human beings throughout history have been tortured and executed, who didn't have the comfort of being an immortal deity. (assuming you believe that part of the story).