Hey Elliott,
first of all, thank you for the purchase!
The portfolio tag archive page template does not contain a sidebar by default, which means that a back-end switch is not envisaged by the theme (mostly for aesthetic purposes). However, the sidebar can be added to the template by adding one line of code to the “taxonomy-tagportfolio.php” template file: the “get_sidebar()” tag, right before the footer call.
Sincerely,
Andrew / Satori Studio