Private Portal End User Signup - notify Admin to authorize the account if not partner/employee

When using a private portal the "end user" can attempt to create an account on there own.   If the end users company is setup up as a partner or employee they can proceed to auto-register on the portal.  However, if they are not set up the system lets them proceed as if they are creating an account but nothing happens.  This is causing confusion and frustration with our customers.

Potential Options:

1. Notify user they must contact the admin aka the reply to email setup on the Idea Portal the user is attempting to gain access to and that the admin must create the user. 
2. **  Allow the user to input the information in the request form and do the following:  (Note Preferred Method)) 
   1. Create user but make them inactive in the system
   2. Notify the Admin that the User has been created
   3. Allow Admin to "Activate" the user which includes sending the activation link  
3.  Add the ability to HIDE the Create user form. 

We have the Private Portal embedded into our Main Customer Portal, however, we do not want to make this a public portal as we need to control access to the ideas platform.  

Thanks for the consideration and feel free to reach out with any questions!