Some calculation beforehand helped. Orange has 52 military units and 23 villagers. Teal has 24 military units (including 2 warships) and 12 villagers (including 2 fishing ships + 1 trade cog). Luckily some of the 100 kills can be made up for with the enemy units you kill along the way. There is no way you could kill all the villagers because they will run around so much, but you have to get rid some of them to get enough.