I feel like whole concept of war effort is intended for majority of server to contribute and complete it.
Now if your plan is to release new patch, no matter if war effort is done or not, you put quite unrealistic task for players who are on Scepter quest.
Having ultimatum to receive rewards only if war effort is complete, you need to have in mind only handful of people are going to be doing event which was made for hundreds and thousands of players.
Getting couple of gold and some reputation for turn ins is not enough to make players on this server be part of war effort.
Just a quick showcase in math regarding this situation:
-lets say 10 people farm every day 2k Wool Cloth ( 1k is even a lot per day)
-20k a day means 12 and half days to complete Wool Cloth (250k)
So that is only 1 material for 12.5 days.
Required materials need to go down in quantity just based of how many players are doing it.