That could be fine. the simplest “everyone can be happy” solution there is one server is called hardcore. I’d just take the name that leave no confusion. A new pve realm is made and the name shall be…
Hardcore
No wow lore to find a clever name. Hardcore…no guessing what it is then.
that Add on does all the details stuff.
They just need to name the server Hardcore server to make it almost idiot proof.