With this Add-on for Super Forms you can password protect your forms from being submitted. You will also be able to hide the form from logged out users, and also from specific user roles. You can also display a message based on these conditions to the user.
Demo https://codecanyon.net/item/super-forms-password-protect-user-lockout-hide-addon/19604086
Downloadhttps://www.filecad.com/ihnM/Super-Forms---Password-Protect-&-User-Lockout-v1.0.6.rar