This page describes how to use Lenses approval requests.
To enable Approval Requests for a group, grant the group Create Topic Request permission. When a user belonging to this group creates a topic it will be sent for approval first.
To enable approval requests, create a group with, or add to a group, the Create Topic Request permission to the data namespace.
Go to Admin->Audits->Requests, select the request, and click view.
Approve or reject the request. If you Approve the topic will be created.