Add meta value to custom post type on publish

I have a client who is requesting that all posts of a certain custom post type (called 'custom-jobs') be set to automatically be included in the sitemap in the Yoast SEO plugin.

I found that in order to do this, the post needs a meta key of '_yoast_wpseo_sitemap-include' with a value of 'always'. So I attempted to call a function using the {status}_{post_type} hook as follows:

function on_jobs_publish( $post_ID ) {
    global $wpdb;
    $wpdb->insert( 
        'iCrewzWp_postmeta', 
        array( 
            'post_id' => $post->ID,
            'meta_key' => '_yoast_wpseo_sitemap-include',
            'meta_value' => 'always'
        ), 
        array( 
            '%d',
            '%s',
            '%s'
        ) 
    );
}
add_action(  'publish_custom-jobs',  'on_jobs_publish', 10, 1 );

This almost works. It adds the meta info to the DB, but the post_id is always set to 0. I've tried passing and using $post and $ID variables as well with no luck. Any idea how I can pass the custom post's id into this function so the meta info is associated with the post that was published?