The moderation queue you are searching for is no longer within the admin console. It has been moved out to the moderators own clearspaceX page.
After setting the moderation option within the selected Space/Community via the admin console, go ahead and submit a thread.
Then, to get to the moderation queue, login to ClearspaceX as the admin -> Go to your profile (either by clicking on avatar, or by navigating Your Stuff -> Profile) -> On right side of page under 'Actions' you should see 'Moderation'.
That is where the threads that are awaiting moderation should be.
Thanks. I would have never found it there. Ever.
Now I doubt we'll actually use it (our forums are running great with only post-facto moderation), but it might be useful to file a bug for your documentation. Thanks.