Hi Rick,
Yes caching could be one option.
But here it seems you have autopromote=true turned on for
your room. So, any user who comes in as guest is getting
autopromoted to presenter role and is getting all controls. You can
change this property either through dev console by logging into
your room or through programmatically in your application by
changing RoomSettings.
LoginDialog.mxml actually has code that sets autopromote=true
and so you are seeing full control when you are going in as guest
since you are getting promoted to presenter role.
Thanks
Hironmay Basu