This is a new error to me, haven't run across it in any Tableau Server for Linux beta or production cases. Would you mind opening up a Tableau Technical Support case? They can take a deeper look, figure out how to resolve the error, and then catalog it in case any future users run into the same issue
Unfortunately, I have no answer to this question if others encounter it. I did an entire server wipe and reinstall (centOS), and it seems to be working find. No issues with AD authentication.