I think it would be best to reduce and/or remove the ability for the defending team in wars to get their specials and possibly even remove missing. I know, it sounds extreme but hear me out.
- The defender isn't there to see it not happening.
- The attacker is there to see their attacks miss and cost them the fight.
- The attacker is there to see the enemy get 2 specials in one fight and them consistently get 0 specials over the coarse of their 5 attacks in the war.
- You could make attackers unable to miss and defenders unable to get their specials and cut the attacker's chance of getting their special in half to balance it out. This way the attacker is not going to be enraged because of pure chance and they'll know that it's because they were out-played and/or just don't have the monsters strong enough to win.
The only potential downside I could see to this is that it would shine an even bigger spotlight on the fact that match-making in war is very commonly one-sided (we either win by a ton or lose by a ton, it's rarely in-between).