Cannot query custom post type taxonomy from theme options array

by

You create a new query and assign it to $my_qry, but you never loop over those results. See the codex page for WP_Query, the loop has to reference your new query object:

$my_qry = new WP_Query($args);
if ( $my_qry->have_posts() ) :
    while ( $my_qry->have_posts() ) :
        $my_qry->the_post();
        // etc..
    endwhile;
endif;