You do not have to be the meeting organizer in order to have Powow join your meeting. However, we encourage you to communicate with the meeting owner and other attendees if you are including the Agent in a meeting.
To include Powow in a meeting invite which you do not own, duplicate the invitation you received and send it to firstname.lastname@example.org. Or send an invite using the invite form in Powow web application. In Powow, you will now be the meeting owner.
Don't forget to CC other meeting participants that are members of your Powow organization so they automatically have access to the meeting once it's complete!