The foul odor that caused the narrator and Thompson to flee into the cold is the Limburger Cheese. Of course they thought it was the rotting corpse but the pine box did not contain a dead body, instead inside were a bunch of guns.
I’m pretty sure this is true
Katniss volunteers herself instead of her sister. This is shocking because Katniss knows this is her fate, but she protects her sister by accepting her own fate. She doesn't want her sister to die.
D the main character is trying to navigate difficult life choices