Test Mode on Wisembly is a very useful option when you are repeating your remote events/meetings on Wisembly. 

By enabling this option, you activate the camera and audio of your integration (Zoom, Webex, Wisembly Visio...) only for animators and platform administrators. This is because participants will not have access to the Visio as long as the test mode is enabled. 

See this article to assign the role of an administrator or facilitator to a participant.