I assume that the password is the MySQL password for the zenoss user on the new system. Since that is the password that will login to MySQL on that system.
I tried these two commands, substituting the server and password.
I still receive the same error when I try to do a restore. Even if I supply the password on the command line.
zenrestore -v --file=/opt/zenoss/backups/zenbackup.tgz --zodb-password=mysqlpassword --zepdbpass=mysqlpassword