I believe the Geneva Protocol separately forbids sending surströmming to the enemy camp as the worst sort of atrocity. What kind of terrible circumstances could have driven Eila and Sanya to resort to such desperate measures? Even the Neuroi don't deserve that!
Reminds of that time in 91:an where the titel character loaded a mortar with Surströmming after a jackass in the troop swapped out the ammo. Karma did the rest.