Removing Azure AD User profile from workstation

I'm not making much progress on https://www.experts-exchange.com/questions/29174726/Moving-one-and-only-user-from-Azure-AD-and-keeping-Office-365-OneDrive.html
So, I thought I might refine the question and make better progress.

I have one workstation that I need to get working as intended.  It all has to do with the user logon.
One user profile is joined to Azure AD and I want to get rid of it.
There are other user profiles that are local users.

But, when I go to Disconnect the account connected to Azure AD, it asks for an alternate account WITH AN EMAIL ADDRESS.
None of the local accounts have this relationship.

How should I proceed?
I have all the privileges I need but this is a tangled mess IMHO.