cannot drop item on death with custom enchantment

I have made a new enchantment and I want to make an entity, slain by a weapon with this echantment, have a chance to drop its spawn egg.

Now I have this class with my @ForgeSubscribe above onDeath:

http://paste.minecraftforge.net/view/40be8997

And my custom enchantment is here:

http://paste.minecraftforge.net/view/a89dfd2f

If you would want to see my @Mod file(probably not, because the WorldEvents class works, but here it is):

http://paste.minecraftforge.net/view/be0d5688

I currently have it dropping skulls, just to test this, but eventually I'd like to add a random chance to drop its spawn egg.

I think the error lies in the fact that EnchantmentHelper.getEnchantmentLevel(SquazerMod.vawku.effectId, wpn) returns 0, which it shouldn't, as I am killing mobs with a vawku IV enchanted sword...