VMs not being added to host pool or AD

Thanks for the tips.  The session hosts are joining to our on-prem Active Directory.  I did some more poking around and found that after 3-4 hours or so the RDagent and the RDagentbootloader eventually get installed.  The error message for this is: "message": "Provisioning of VM extension Microsoft.PowerShell.DSC has timed out. Extension provisioning has taken too long to complete. The extension did not report a message.

It takes about 2 hours for the Microsoft.PowerShell.DSC to have the error message and timeout, then after another 2-3 hours, it eventually completes successfully.  I guess it continues to try. My colleague mentioned that DSC is like that, it'll keep trying. 

The second part of it not joining the domain, I found that the "joindomain" extension is being applied to the VM's.  In the "Extensions + applications" section of the VM's properties, the "joindomain" is not listed at all. So it seems like its not even attempting it.  I checked on a couple of the new VM's and there isn't any log in C:\WindowsAzure\Logs\Plugins.