What necromancers have "traditionally" done is not the issue.
Yes it is. Like it or not, words mean things.
If I say I'm serving pizza, but I give you a patty of ground beef with a slice of melted cheese on a bun, people will look at me funny. Yes, burgers and pizzas are both generally comprised of a form of bread, some meat products, and some cheeses, but that doesn't mean you get to call one thing another and not get the hairy eyeball from the populace.

If you want something that doesn't do what most folks think of when you say, "necromancer", why call it a necromancer? You got a new fictional thing, give it a new fictional name!