To be honest, I’m not seeing anything.
The only suggestions I can make are to remove this line that appears above the new query
<?php wp_reset_query(); ?>
It shouldn’t interfere, but it’s not needed there, that needs to be after the <?php endif; ?> of your nested query.
The other suggestions is to name the new query something else, it could be the $query is a problem, but there’s no reason I know of that it should be.
<?php
$args = array(
'post_type' => 'county',
'posts_per_page' => -1,
'meta_query' => array(
'key' => 'state',
'value' => $post->ID,
),
);
$county_query = new WP_Query($args);
// you need to refer to the new query object you created above
if($county_query->have_posts()) : ?>
<ul>
<?php while($county_query->have_posts()) : $county_query->the_post(); ?>
<li><?php the_title(); ?></li>
<?php endwhile; ?>
</ul>
<?php endif; ?>
