I would like to think that this is up to the GM. I.E., the Shadow World campaign is yours, so asking on new perspectives is both good and bad for you.
My take: I don't use the rules in Elemental Companion as of yet, so I don't have to deal with it. However, I think it would be okay for a Nomenist sorcerer to exist. To destroy something, you have to at least know it's name.
Although it's easier to destroy than to create -- at least so the saying goes (personally, it's faster to destroy than to create, but not any easier).