I made up a name for an RPG character, and then started using it across the internet.

Then I found out that someone else had already made the name a few years before me and was already doing that.

Even unique names that aren't at all dictionary words are at risk of collision. I think the smarter tactic is to accept that you won't get that same nickname everywhere, and just have a few alternatives that you'll use if necessary. Complaining to the masses that a name is already taken isn't going to work.