Hi Tez,
I also encountered the issue as yours: the field is somehow hidden, I am not sure whether the functionality is still under development so it was set to be hidden by system.
In form editor, you could display the field by default.

Or run custom function at OnChange event of "Do you want to stream this event":
if the field value equals to true, set the hidden field to be visible with code;
if the field value equals to false, hide the field again.


function unlockField(executionContext) {
var formContext = executionContext.getFormContext();
var isTeamEnabled = formContext.getAttribute("msevtmgt_streamingenabled").getValue();
if (isTeamEnabled === true) {
formContext.getControl("msevtmgt_recordingforproducersandspeakers").setVisible(true);
} else {
formContext.getControl("msevtmgt_recordingforproducersandspeakers").setVisible(false);
}
}
(If necessary, please add run the function at OnLoad event of form.)
Result:

Regards,
Clofly