Showing list of posts including custom taxonomy terms - php

Question

I'm working on a WP_Query loop that is suppose to show the list of posts in a following way
+ Custom taxonomy term 1
++ Post 1
++ Post 2
+ Custom taxonomy term 2
++ Post 1
++ Post 2
So in general it will work for CPT called 'career'. In a real life my custom taxonomy (job-category) is like: Drivers, Logistics, HR etc. And to each of such taxonomy/category I've got created specific posts. There is also a custom taxonomy called job-country which suggests the territory.
To achieve the way of showing my posts I am using the following code:
<?php
$terms = get_terms([
'taxonomy' => 'job-category',
'hide_empty' => true,
'orderby' => 'count',
'order' => 'DESC'
]);
usort( $terms, function( $a, $b ) {
$a_ste = (int) get_term_meta( $a->term_id, 'stick_to_end', true );
$b_ste = (int) get_term_meta( $b->term_id, 'stick_to_end', true );
if ($a_ste == $b_ste) return 0;
return ($a_ste < $b_ste) ? -1 : 1;
} );
if ($terms) { //categories exists
foreach ($terms as $category) { ?>
<h2 class="category-title">
<?= $category->name ?>
</h2>
<?php
$posts = get_posts(array(
'posts_per_page' => -1,
'post_type' => 'career',
'tax_query' => [
[
'taxonomy' => 'job-category',
'field' => 'term_id',
'terms' => $category->term_id,
]
]
));
if ( $posts ) {
foreach( $posts as $post ) {
setup_postdata( $post );
include 'JobListThumb.php';
};
wp_reset_postdata();
}
}
} else { //no categories
$posts = get_posts(array(
'posts_per_page' => -1,
'post_type' => 'career'
));
if ( $posts ) {
foreach( $posts as $post ) {
setup_postdata( $post );
include 'JobListThumb.php';
};
wp_reset_postdata();
}
}
?>
And it works. But because of certain reasons (working on an ajax filtering function) I need to achieve the same thing using traditional wp_query.
This is what I've got:
$args = array(
'orderby' => 'date', // we will sort posts by date
'order' => $_POST['date'], // ASC or DESC
'post_type' => 'career',
);
// for taxonomies / categories
if( isset( $_POST['categoryfilter'] ) && isset( $_POST['taxonomyfilter'] ))
$args['tax_query'] = array(
'relation' => 'AND',
array(
'taxonomy' => 'job-category',
'field' => 'id',
'terms' => $_POST['categoryfilter']
),
array(
'taxonomy' => 'job-country',
'field' => 'id',
'terms' => $_POST['taxonomyfilter']
)
);
// if you want to use multiple checkboxes, just duplicate the above 5 lines for each checkbox
$query = new WP_Query( $args );
if( $query->have_posts() ) :
while( $query->have_posts() ): $query->the_post();
echo '<h2>' . $query->post->post_title . '</h2>';
endwhile;
wp_reset_postdata();
else :
echo 'No posts found';
endif;
die();
But I've stucked in a place - how to add those terms / elements to the query? Obviously cannot mix get_terms with wpquery by simply copying instead echo'ing the title.
Do you have any suggestions how to solve this?