Unable to see sidebars

Hi I am trying to use this on a client’s site. I did not do the theme they are using but it is a modified version of 2011 (not a child theme).

Installation and activation went normally. I created the custom field and it shows correctly but the only sidebar I am allowed to choose from is the “main sidebar” none of the other registered sidebars show in the dropdown menu. (they do show on the widgets page).

Any clues as to what may be causing this?

http://wordpress.org/extend/plugins/advanced-custom-fields-widget-relationship-field-add-on/