It's always good to wet down your topdressings too.I think @Fermented_Fruitz is correct. You don't have to mix the nema's with water. It's just to make sure you have a good distribution.
So if you mix the nematode powder with your topdressing well and then divide this over the soil, you probably will get the same result.
@Lil Dab
If you're worried about your moisture level in the EB being too much to add water with your todes, just take ALL your compost you're going to add today, wet it fully, add the todes, mix fully and distribute to your girls. I basically used that method to give my flower nutes to the outdoor 9ft Asian Haze with no issues.