Have you tried enclosing the AD group with double-quotes ("Tableau - AQ Reporters")? In the log I see the AD group name begin with a single quote and end with TWO single quotes.
I have mentioned the group name within double-quotes. In the log, it shows with single quote (by default).
Anyways, I have rasied a support ticket with tableau. The response was that it is a limitation for the tabcmd to process the group name with such symbols. Recommended action is not to use such symbols in the AD group and this limitation would be taken care of in any future releases when deemed necessary
Thank you for taking the time to post the response you received from Support, and for marking your question answered. This really helps make the forum a better place!
Thanks for posting the answer, that helps all here. If only more people would do the same...