Sorry, but I didn't read your entire post, but take a look here: VMware KB: Installing vCenter Server 5.5 best practices
From the link above, one of requirements for install vCenter Server is:
- Verify that the system on which you are installing vCenter Server is not an Active Directory domain controller.
There are some links on the internet showing how to install AD DS and vCenter on the same machine, but this is not a supported configuration.