How to render posts via AJAX

I have a calendar and when the user clicks on a date I send a call to the API to load posts from that date. No matter what I do I can’t render the posts with the loop.
Here is what I have:

function get_events(WP_REST_Request $request)
{

    //ob_start();
    $paged = 1;//(get_query_var('paged')) ? get_query_var('paged') : 1;
    $date = '';
    $event = "";
    $event_date = $request["event_date"];

    $args = array(
        'post_type'      => 'event',
        'posts_per_page' => 3,
        'paged'          => $paged,
        'meta_key'       => 'event_date',
        'meta_value'     => $event_date,
        'meta_compare'   => '>=',
        'orderby'        => 'meta_value',
        'order'          => 'ASC'
    );
    //I made sure that there are values here
    $the_query = new WP_Query( $args );

    ob_start();

    get_template_part('events_template');

    $content = ob_get_contents();
    ob_get_clean();
    return $content;
}

Here is my events_template:

<div class="posts-container">
    <?php if ( have_posts() ) : while ( $the_query->have_posts() ) : $the_query->the_post(); ?>
        <div>
            <?php
                //Here we group events by event_date and add the date at the top.
                $event_date =  get_post_meta( $post->ID, 'event_date', true );
                if ( $event_date != $date )
                {
                    $event_date_formatted = date( 'l, F jS, Y', strtotime( $event_date ) );
                    echo "<p class='page-header'><strong>$event_date_formatted</strong></p>";
                    $date = $event_date;
                }

            ?>
            <div class="event ath-card">
                <h4><?php the_title(); ?></h4>
                <p><?php echo get_post_meta( $post->ID, 'event_location', true ) ?></p>
                <p><?php echo get_post_meta( $post->ID, 'event_details', true ) ?></p>
            </div>
        </div>
    <?php endwhile; endif; ?>
</div>

<div class="loader text-center hidden">
    <i class="fa fa-spinner fa-pulse fa-3x fa-fw"></i>
</div>

<div class="div pagination-container text-center">
    <?php
        next_posts_link( '<button class="ath-btn ath-btn-info">LOAD MORE</button>', $the_query->max_num_pages );
    ?>
</div>

It renders all the content that is not inside the if/while statements.