Yes this is where I would have made the changes. However since all this is greyed out and there is no landscape(network) diagram this is of no help in determining if it is actually changed properly. I realize you do not want to include specifics of your installation in the public forum. In this case it might be best to submit a support ticket and share all this info including logs of unsuccessful logins to Support. They will need landscape diagram copies of the cluster configurations directory configurations and the application log. They should also be given the actual URL's you use to login.
Regards,
Gary