How to use Identity First with both Organizations B2B and personal accounts B2C

We’ve got a website with both B2B and B2C users. Everyone uses the same URL to access the application.
B2B Users only belong to one organization ever.
What I want to achieve is the following:

  1. User (B or C) clicks Sign In.
  2. User enters email address.
  3. If user belongs to an Organization => redirect to Organization login page
  4. Otherwise send to B2C login page

Our Organizations will use DB connections only, i.e. no Enterprise connections.

I’ve done a lot of reading, and I’ve read about Home Realms Discovery, but this only works for Enterprise Connections.

I’m also aware of the Organization Prompt which asks the user to enter their Organization Name. We don’t like this as this may be confusing to users. Some of our B2B customers have already trouble remembering their username, let alone their Organization name.

Of course I could build a custom page in our application to achieve this, i.e. they enter email address, I call the management API, and then redirect correspondingly. However, this is a security risk and I’d rather use Auth0 managed pages.