Hey Spencer,
please make sure that you are using the slider alias and there are no typos: the “Header revolution slider” field in the “Revolution Slider” tab of the Theme Options panel should contain the alias of an existing slider; the alias is a unique lowercase identifier given to a slider, which you can see by clicking on the green “Slider settings” button next to the respective slider, and checking the “Slider Alias” field. In case the above information does not help remove the error message, I will need to ask for access to your back-end – you can send the login and password to support@satoristudio.net (no disclosure guaranteed).
Sincerely,
Andrii / Satori Studio