I think I know what you mean now. When viewing the discussion index, the previewed discussions list doesn't have inline moderation controls. These controls are only available in the full list view of the discussions list. However, if there are less than 5 discussions, there is no link to the full view. If you visit a discussion hoping for an alternative delete method, there is no delete link from within the discussion.
Additionally, there were a few bugs where:
- A discussion owner, without moderator permissions to delete discussions, but who has permission to delete his/her own discussions, would never be allowed to delete his own discussions.
- The checkbox to delete a discussion would only appear if a moderator had permission to delete his/her own comments.
- The checkbox to delete a discussion would never appear if the discussion was originally started from a topic suggestion.
Thus, there are numerous issues related to your OP that must be resolved by a new release.
In the mean time, you should be able to see the option to remove discussions by manually going to ?do=comments&action=list