I can't seem to find a way to query the default group name from API. I know the default name is default but if the server renames this to another name then I have no way of knowing what the group is.

The server is unable to rename it unless they hardcode the change - which I don't think the API accounts for. If they try, LP creates a new default group.

Ah yes, I see the wiki states display name here

https://github.com/lucko/LuckPerms/wiki/Default-Groups#keep-using-the-default-group-but-just-modify-the-display-name

So this is a non-issue.

Thanks!

No worries!