Hi,
I see that you tried to reset the password fom serial connection,
The "restore defaults" is the command that restores the default configuration to the controllers.
But to do that are you able to successfully login with serial connection to either of the controller?
If so we can try few commands.
if the password is not set,you could try default login credentials
Username Password Roles
monitor !monitor Monitor (view only)
manage !manage Monitor, Manage (view and change)
Let me what is the current status of SSH and serial connection access to both controllers?
Thanks