PozHonks (et al)- you just need to replace lines 48 to 54 with:
update_post_meta( $post_id, '_woocommerce_simple_product_badge_title', esc_attr( $title ) );
update_post_meta( $post_id, '_woocommerce_simple_product_badge_class', esc_attr( $class ) );
You don’t need the if-then-else conditionals at all.
