You are not winning the Plasma match up anyways. Most of the time they will favor attacking with Lugia EX anyways to take 2 Prizes instead of one on your Miltanks that you should be attacking with instead of Empoleons.
There’s a 1 in 53 chance that your single Dusknoir will be Prized (probably a little more than that because there are 6 Prizes but I don’t feel like doing math) and when it is you run Town Map anyways. You could make the same argument for adding 2 Exeggcute but you don’t because even if it is Prized it isn’t the end of the world. Also you play 4 Rare Candy, so you’ll likely be using one for Dusknoir, especially since you also have Prinplups. I don’t have a big problem with running a Dusclops, but the 2nd Dusknoir is certainly not needed and I’d go as far to say it’s pretty bad.