How to join a client PC to WS2012E R2 that's already a member of another enterprise domain using the skip domain join registry entry?

In WSE12 R1 you can install the connector application on a Windows 7 PC that has already been joined to a corporate domain using the skip domain registry key:

reg add "HKLM\SOFTWARE\Microsoft\Windows Server\ClientDeployment" /v SkipDomainJoin /t REG_DWORD /d 1

Upon doing so, the client PC is then able to perform client backups to the WSE12 R1 server but remains a member of the original corporate domain.  This is no longer possible when using this registry key when installing the Windows Server 2012 Essentials R2 connector

Is anyone aware of a way to install the WSE12 R2 connector and skip domain join without first leaving the corporate domain? 

I am avoiding moving to WSE12 R2 until I can figure out a way to accomplish this.