Hello Walter,
The configuration that you have mentioned has not been tested by our internal QA team. However, I believe that as long as the group is visible in Active Directory it should be able to manage it. If you have evaluated WebDir and run into an issue with the afore mentioned configuration, please send an email to support@imanami.com or call 925-371-3000 option 3 to assist you.
Looking forward to hearing from you soon.