Multiple meta value orderby clauses in a WP_Query

This is likely not the “ideal” approach, but this works for me, and now I can move on to other things. If someone has a better option, I’d love to hear it, thank you.

$base_args = [
    'post_type'   => 'crowdfunding',
    'numberposts' => 30,
    'posts_per_page' => '50',
];

$meta_query = array(
    array(
        'key'        => 'campaign_start_date',
        'compare'    => '<=',
        'value'      => $in_three_days,
    ),
    array(
        'key'        => 'campaign_end_date',
        'compare'    => '>=',
        'value'      => $today,
    ),
);

$args = array(
    'meta_key'      => 'campaign_end_date',
    'orderby'       => 'meta_value_num',
    'order'         => 'ASC',
    'meta_query'    => $meta_query,
);

$crowdfunding_posts = new WP_Query(get_posts(array_merge($base_args, $args)));

usort($crowdfunding_posts->query, function($a, $b) {
    return strcasecmp( 
        $b->campaign_is_featured,
        $a->campaign_is_featured, 
    );
});

And now it’s behaving just like I want it to. I can take the little hit for the sort because the page itself is also being cached.