User Dashboard - Include Custom Fields as Columns

Thanks for this. I'm not much of a coder but I've changed the code you supplied as follows but it doesn't work for me:

use MetaBox\Support\Arr;
class My_Dashboard {
    private $query;
    private $edit_page_atts;
 
    public function __construct() {
        add_shortcode( 'custom_frontend_dashboard', [ $this, 'shortcode' ] );
    }
 
    public function shortcode( $atts ) {
        /*
         * Do not render the shortcode in the admin.
         * Prevent errors with enqueue assets in Gutenberg where requests are made via REST to preload the post content.
         */
        if ( is_admin() ) {
            return '';
        }
 
        if ( ! is_user_logged_in() ) {
            return esc_html__( 'Please login to view the dashboard.', 'mb-frontend-submission' );
        }
 
        $this->edit_page_atts = $this->get_edit_page_attrs( $atts['edit_page'] );
        if ( is_wp_error( $this->edit_page_atts ) ) {
            return '<div class="rwmb-error">' . $this->edit_page_atts->get_error_message() . '</div>';
        }
 
        $atts = shortcode_atts( [
            // Meta box id.
            'id'           => $this->edit_page_atts['exam'],
 
            // Edit page id.
            'edit_page'    => '42',
 
            // Add new post button text
            'add_new'      => __( 'Add New', 'mb-frontend-submission' ),
 
            // Delete permanently.
            'force_delete' => 'false',
 
            // Columns to display.
            'columns'      => 'title,date,status',
 
            // Column header labels.
            'label_title'   => __( 'Title', 'mb-frontend-submission' ),
            'label_date'    => __( 'Date', 'mb-frontend-submission' ),
            'label_status'  => __( 'Status', 'mb-frontend-submission' ),
            'label_actions' => __( 'Actions', 'mb-frontend-submission' ),
 
            // Link action for post title (view|edit).
            'title_link'    => '',
 
            // Flag to hide/show welcome message.
            'show_welcome_message' => 'true',
        ], $atts );
 
        ob_start();
        $this->query_posts();
 
        if ( $atts['show_welcome_message'] === 'true' ) {
            $this->show_welcome_message();
        }
 
        $this->show_user_posts( $atts );
 
        return ob_get_clean();
    }
 
    private function query_posts() {
        $this->query = new WP_Query( [
            'author'                 => get_current_user_id(),
            'post_type'              => $this->edit_page_atts['post_type'],
            'posts_per_page'         => -1,
            'post_status'            => 'any',
            'fields'                 => 'exam_name','post_duzf91pjqvb','start_date','start_time','end_date','end_time',
            'no_found_rows'          => true,
            'update_post_meta_cache' => false,
            'update_post_term_cache' => false,
        ] );
    }
 
    private function show_welcome_message() {
        $post_type        = $this->edit_page_atts['post_type'];
        $post_type_object = get_post_type_object( $post_type );
        $user             = wp_get_current_user();
        $query            = $this->query;
 
        $message  = '<h3>'. esc_html( sprintf( __( 'Howdie, %s!', 'mb-frontend-submission' ), $user->display_name ) ).'</h3>';
        $message .= '<p>'. esc_html( sprintf( __( 'You have %d %s.', 'mb-frontend-submission' ), $query->post_count, strtolower( $post_type_object->labels->name ) ) ).'</p>';
        $output   = apply_filters( 'mbfs_welcome_message', $message, $user, $query );
        echo $output;
    }
 
    private function get_edit_page_attrs( $edit_page_id ) {
        $edit_page = get_post( $edit_page_id );
        $pattern   = get_shortcode_regex( ['mb_frontend_form'] );
 
        if ( ! preg_match_all( '/' . $pattern . '/s', $edit_page->post_content, $matches ) || empty( $matches[2] ) || ! in_array( 'mb_frontend_form', $matches[2] ) ) {
            return new WP_Error( 'mbfs-no-edit-page', __( 'Something is not right with the shortcode on page ID: ', $edit_page_id ) );
        }
 
        // Get shortcode attributes.
        $key            = array_search( 'mb_frontend_form', $matches[2] );
        $shortcode_atts = explode( ' ', $matches[3][ $key ] );
 
        // Get only 'id' and 'post_type' attributes.
        $attributes = [
            'id'        => '42',
            'post_type' => 'exam',
            'url'       => get_permalink( $edit_page ),
        ];
        foreach ( $shortcode_atts as $attribute ) {
            $attribute = explode( '=', $attribute );
 
            if ( in_array( $attribute[0], ['id', 'post_type'] ) ) {
                $attributes[ $attribute[0] ] = str_replace( ['"', "'"], '', $attribute[1] );
            }
        }
 
        return $attributes;
    }
 
    private function show_user_posts( $atts ) {
        $this->enqueue();
        ?>
        <a class="mbfs-add-new-post" href="<?= esc_url( $this->edit_page_atts['url'] ) ?>">
            <?= esc_html( $atts['add_new'] ) ?>
        </a>
        <?php
        if ( ! $this->query->have_posts() ) {
            return;
        }
        ?>
        <table class="mbfs-posts">
            <tr>
                <?php
                $columns = Arr::from_csv( $atts['columns'] );
                if ( in_array( 'title', $columns ) ) {
                    echo '<th>', esc_html( $atts['label_title'] ), '</th>';
                }
                if ( in_array( 'date', $columns ) ) {
                    echo '<th>', esc_html( $atts['label_date'] ), '</th>';
                }
                if ( in_array( 'status', $columns ) ) {
                    echo '<th>', esc_html( $atts['label_status'] ), '</th>';
                }
                ?>
                <th><?= esc_html( $atts['label_actions'] ) ?></th>
            </tr>
            <?php while( $this->query->have_posts() ) : $this->query->the_post(); ?>
                <tr>
                    <?php if ( in_array( 'title', $columns ) ) : ?>
                        <?php
                        if ( $atts['title_link'] === 'edit' ) {
                            $title_link = add_query_arg( 'rwmb_frontend_field_post_id', get_the_ID(), $this->edit_page_atts['url'] );
                        } else {
                            $title_link = get_the_permalink();
                        }
                        ?>
                        <td><a href="<?= esc_url( $title_link ) ?>"><?php the_title(); ?></a></td>
                    <?php endif; ?>
 
                    <?php if ( in_array( 'date', $columns ) ) : ?>
                        <td align="center"><?php the_time( get_option( 'date_format' ) ) ?></td>
                    <?php endif; ?>
 
                    <?php if ( in_array( 'status', $columns ) ) : ?>
                        <td align="center"><?= get_post_status() ?></td>
                    <?php endif; ?>
 
                    <td align="center" class="mbfs-actions">
                        <a href="<?= esc_url( add_query_arg( 'rwmb_frontend_field_post_id', get_the_ID(), $this->edit_page_atts['url'] ) ) ?>" title="<?php esc_html_e( 'Edit', 'mb-frontend-submission' ) ?>">
                            <img src="<?= MBFS_URL . 'assets/pencil.svg' ?>">
                        </a>
                        <?= do_shortcode( '[mb_frontend_form id="' . $this->edit_page_atts['id'] . '" post_id="' . get_the_ID() . '" ajax="true" allow_delete="true" force_delete="' . $atts['force_delete'] . '" only_delete="true" delete_button="<img src=\'' . MBFS_URL . 'assets/trash.svg' . '\'>"]' ); ?>
                    </td>
                </tr>
            <?php endwhile ?>
        </table>
        <?php
        wp_reset_postdata();
    }
 
    private function enqueue() {
        wp_enqueue_style( 'mbfs-dashboard', MBFS_URL . 'assets/dashboard.css', '', MBFS_VER );
        wp_enqueue_script( 'mbfs', MBFS_URL . 'assets/frontend-submission.js', array( 'jquery' ), MBFS_VER, true );
    }
}
 
new My_Dashboard();

Where an I going wrong?

Thanks