/**
 * Load different template for content as per conditions.
 *
 * @param $templates
 * @param $slug
 * @param $name
 *
 * @return mixed
 */
function load_alternate_template( $templates, $slug, $name ) {

	if ( $name == 'content' ) {
		$name         = 'alternate-content';
		$templates[0] = $slug . '-' . $name . '.php';
	}

	return $templates;

}
add_filter( 'testimonials_widget_get_template_part', 'load_alternate_template', 15, 3 );