Skype Business for Mac - Contacts and groups not showing/can't be added

Using Office 365, Outlook 2016 for Mac (Insider Fast - 15.33.170321), and Skype Business for Mac (Insider Fast - 16.5.175).  Things previously were working, but went wonky.  Logged out, removed profile, then did a full Skype (and Lync) uninstall per directions.  Rebooted and reinstalled Skype Business for Mac then updated.

In the Skype client the contract groups and contacts I previously had are not displaying.  The option to add a group and/or a contact is greyed out.  Using the Skype Business for IOS client my contact groups and contacts are showing up.  I imagine if I ran the Windows client they would show up as well.

Is there some setting locally on my Mac that is preventing the download from Skype of my contacts?  I've confirmed (via the Calls screen) that my Exchange credentials are entered properly.  After installing and going to that screen for the first time is asks for (and I provide) my Exchange credenitals to sync.  I am able to get a synced voicemail from Exchange.

I've left the system logged in for 12+ hours as I'd seen something about AD Sync taking a long time.  When I lookup contacts I'm now seeing AD details and names for contacts, not just e-mail addresses.

What else should I try?