You can manually approve your registrants before sending them a confirmation email. To do so, you will need to configure your campaigns to handle this additional step:
For the Registration Trigger Campaign:
Go to the Event and click the Members tab. This tab displays all the people who have filled out the form. Their status should be set to Pending Approval.
Use the filter at the top of the grid to view only the people with a status of Pending Approval.
Select the people that you wish to register (Shift-click, Control-click, or Select All).
From the menu, click Change Status. Select Registered, Rejected, or any other applicable status.
If a person ends up not being registered but rather set to the status Registration Error, it’s not too late to recover.
Marketo automatically pulls in the attendance information at approximately 11pm Pacific each night. To manually update attendance information, click Refresh from Webinar Provider under Event Actions.