Well, I tried using the direct installation with adjoin. Unfortunately, that failed too with the error "No writable domain controllers found.". I suspect that this is also related to the subnet issues.
Log below:
root@nmsep01-ic1-bfi:~/centrify# adjoin -w -u milo-admin -V corp.xxx.com milo-admin@CORP.xxx.COM's password: Options ------- Precreate: no Compatible with 2.x/3.x: no Enable Apple Scheme to generate UID/GID: no domain: corp.xxx.com user: milo-admin@CORP.xxx.COM container: null computer name: nmsep01-ic1-bfi Pre-Windows 2000 name: nmsep01-ic1-bfi DNS Host Name used for dNSHostName attr: null zone: Auto Zone server: null zoneserver: null gc: null upn: null noconf: no set time: yes force: no forceDeleteObj: no forceDeleteObjWithDupSpn: no trust: no des: no self-serve: no respectEncInConf: no respectSpnInConf: no use ldap to create computer object: no license type: null createComputerZone: no forceDeleteExistingComputerZone: no Setting time Initializing domain settings file to corp.xxx.com Attempting bind to corp.xxx.com(site:) as milo-admin@CORP.xxx.COM on any server Error: No writable domain controllers found. Join to domain 'corp.xxx.com', zone 'Auto Zone' failed.