I am sorry, maybe your superrior brain know what is answer on my question, but I dont know....
dude pay attention you don't need to be a genious :
if he sacrificed his army was coz: no one else who is capable of attacking the guy from togw could beat his army, so he tricked the togw guy to attack him, went out of the alliance, so they dont give away war points, and now togw can be killed
there is no other reason for comitting such dmmy thing