Hello,
Sorry but I don't quite understand what a Resource Calendar account is... Is it a regular user mailbox that shares its calendar? If that is the case why not use a Resource Mailbox instead of a User Mailbox (a resource mailbox uses a disabled AD user account).
If either of them are true, I don't see why that account should be enabled for Lync.
As for the regular user account, the 'HideFromAddressLists' property works fine from hiding from GAL.
Also a Lync enabled user need to have 3 AD attributes configured in order to be 'enabled' for Lync:
msRTCSIP-PrimaryUserAddress - This attribute contains the SIP address of a given user.
msRTCSIP-UserEnabled - This attribute determines whether the user is currently enabled for Lync Server.
msRTCSIP-PrimaryHomeServer - This attribute enables a user or contact for SIP messaging. It is added to the contact class because in the central forest topology, contact objects, not user objects, are SIP enabled. The valid value is the DN of the Standard
Edition server or Enterprise Edition Front End pool where a user is homed.
I haven't tested this because I wasn't confronted with such a scenario but, if the msRTCSIP-PrimaryUserAddress is removed, then it might not be indexed in the Lync Address Book on the next AD replication process. I think there are some attributes that
are 'mandatory' in order to synchronize the contact from AD and the SIP address might be one of them, but like I said I haven't tried this b