Recently I defederated my domain from Office 365. I followed these steps here.
I ran this command
Convert-MsolDomainToStandard –DomainName brisbanecloud.net –PasswordFile C:\temp\passwords.txt
Interestingly the passwords.txt file remained empty. Old documentation says that it will enter user passwords here.
I tried the command without specifying a password file. It still prompted me for this. End result was this still worked and the domain was defederated.