And…. the answer was actually correct, if you are using the correct functions. As Milo pointed out, it’s wp_enqueue_script
not scripts.
add_action('wp_footer', 'print_my_script');
function print_my_script() {
if(did_action('my_custom_action')) {
wp_enqueue_script('listings');
wp_enqueue_script('isotope');
}
}
Hopefully this helps someone else in need!