get_cat_ID issue, it is supposed to use a name which is not limited to one id

I work on a music website, where I have decided to set an artist as a main category and all their albums as a child category. My lyrics therefore are posts, assigned to an album category. To my knowledge (which is only moderate) this is the way to go, combining stuff with a category meta plugin. So far for the introduction.

So I can have artists that are different, yet have exactly the same artist name. This seems no problem, as I can add them and them using the same name and having a different slug.

The problem I encouter is when using get_cat_ID(‘Not a unique NAME’), I only get the ID of one of my categories using that name. I expected an array of ID’s matching my name, as the specs clearly state using the name.

Besides if what I expect to to get, how can I best obtain my goal to get all id’s of all my categories having a particular name.