I’m running into a similar issue. On line 24 core/scripts/css-js.php from v5.1 of the engima-parallax theme, I see:
wp_enqueue_script('caroufredsel', get_template_directory_uri() .'/js/caroufredsel-6.2.1/jquery.caroufredsel-6.2.1.js', array('jquery'), true, true );
wp_enqueue_script('caroufredsel-element', get_template_directory_uri() .'/js/caroufredsel-6.2.1/caroufredsel-element.js', array('jquery'), true, true );
However, the directory is named carouFredSel (different capitalization), so the Inspect tab of my browser reports a status 404 (not found) when trying to load these. The correct lines should be:
wp_enqueue_script('caroufredsel', get_template_directory_uri() .'/js/carouFredSel-6.2.1/jquery.caroufredsel-6.2.1.js', array('jquery'), true, true );
wp_enqueue_script('caroufredsel-element', get_template_directory_uri() .'/js/carouFredSel-6.2.1/caroufredsel-element.js', array('jquery'), true, true );
Would you update this in the next version of the theme?