wp_insert_post works, but the post isn’t visible in the admin post list or front end

The problem is $postarr["post_status"] = "published"; you should change it to

$postarr["post_status"] = "publish"; // Set it to 'publish', not 'published'

Now, this is a bit off topic, but you may want to omit the following (those are created by the wp_insert_post() by default):

$postarr["post_date_gmt"] = date('Y-m-d H:i:s', time());
$postarr["post_date"] = date('Y-m-d H:i:s', time());
$postarr["post_modified"] = date('Y-m-d H:i:s', time());
$postarr["post_modified_gmt"] = date('Y-m-d H:i:s', time());