Explanation/Reference:
* New-OrganizationRelationship
Use the New-OrganizationRelationship cmdlet to create a relationship with an external Microsoft Exchange Server 2010 and Exchange Server 2013 organization for the purpose of accessing calendar free/busy information or moving mailboxes between on-premises Exchange servers and the Exchange Online service as part of a hybrid deployment.
/The DomainNames parameter specifies the SMTP domains of the external organization. If adding multiple domain names, separate each entry with a comma.
/The FreeBusyAccessEnabled parameter specifies whether this organization relationship should be used for retrieving free/busy information from the external organization. The valid values for this parameter are
$true or $false. The default value is $false.
Incorrect:
* The Set-AvailabilityConfig cmdlet defines two accounts or security groups: a per-user free/busy proxy account or group, and an organization-wide free/busy proxy account or group. These accounts and groups are trusted by all availability services in the current organization for availability proxy requests.
* There is no cmdlet Set-AvailabilityAddressSpace.
Reference: New-OrganizationRelationship
https://technet.microsoft.com/en-us/library/ee332357(v=exchg.150).aspx