I created the account RainbowUnicorn to find this one. I have since found it and I don’t need my old account anymore. Is there a way to delete it?

Normally No. Moderators can rename your account and change your bio.

Would that just illicit that it isn’t being used anymore?

You cannot delete your account from the server, since your past account probably has interacted with other players. If your account would be deleted, those players would have a non-existing account in their games.

In you case it's a level 1 without any games played, but it nevertheless still cant be deleted cause the data linked to your account is needed by other people (or maybe just the server).

Long story short, your account cannot be deleted, so you can just abandon it.

https://www.warzone.com/Profile?p=5983341316