Great thread!
Raises very interesting halachic discussion:
a. Was Damon allowed to offer himself as a replacement should Pythias not return?
b. Once pythias was set free is he allowed to return? is he Obligated?
As for a. I t would seem offering himself with the knolwdge that Damon would return would be allowed (though how can he be sure enough to enter a makom sakana)
as for b. Im not sure IF ythias is Obligated to return though if it is up to him, Im not sure Damon was allowed to offer himself
I keep going in circles