Yes, but you need to customize the code of the Facebook API connector.

Instead of generating automatically a random email address, you should change the code to perform a redirection.

The file is: root/modules/mod_instantfblogin/socials/facebook.php

and the line where the email address is managed is the number 62:
$email = $fbUserProfileArray ['email'] ? $fbUserProfileArray ['email'] : $fbUserProfileArray ['id'] . '@facebook.com';

Best regards