MB Admin Columns with MB Relationships

Hi,

I'm trying to display a relationship in a custom column and I also need it filterable.
I managed to display the column with this code:

add_action( 'manage_assembly_step_posts_custom_column' , 'custom_assembly_step_column', 10, 2 );
function custom_assembly_step_column( $column, $post_id ) {
    switch ( $column ) {
        case 'bunkie' :
            $bunkies = new WP_Query( array(
                'relationship' => array(
                    'id'   => 'bunkies_to_assembly_steps',
                    'to' => $post_id
                ),
                'nopaging' => true,
            ) );

            if ($bunkies->have_posts()) {
                foreach ($bunkies->posts as $index => $bunkie) {
                    $bunkieMetas = get_post_meta($bunkie->ID);
                    echo $bunkieMetas['name_en'][0];
                    if ($index !== count($bunkies->posts) - 1) {
                        echo '<br>';
                    }
                }
            }
            break;
    }
}

I'm using this code to display a dropdown with all options:

add_action( 'restrict_manage_posts', 'filter_assembly_steps_by_bunkie' );
function filter_assembly_steps_by_bunkie() {
    global $typenow;
    global $wpdb;
    if ( $typenow == 'assembly_step' ) {
        $bunkies = $wpdb->get_results( "SELECT * FROM $wpdb->posts WHERE post_type = 'bunkie' AND post_status = 'publish'" );
        $values = [];

        foreach ($bunkies as $bunkie) {
            $values[$bunkie->post_title] = $bunkie->ID;
        }

        $current_bunkie = '';
        if( isset( $_GET['bunkie_id'] ) ) {
            $current_bunkie = $_GET['bunkie_id'];
        } ?>
        <select name="bunkie_id" id="bunkie_id">
            <option value="all" <?php selected( 'all', $current_bunkie ); ?>><?php _e( 'Filter By Bunkies', 'text_domain' ); ?></option>
            <?php foreach( $bunkies as $bunkie ) { ?>
                <option value="<?php echo esc_attr( $bunkie->ID ); ?>" <?php selected( $bunkie->ID, $current_bunkie ); ?>><?php echo esc_attr( $bunkie->post_title ); ?></option>
            <?php } ?>
        </select>
    <?php }
}

But then I don't how to make it sortable. I was using this code before because I used to set a custom field instead of using your relationships plugin:

add_filter( 'parse_query', 'query_filter_assembly_steps_by_bunkie' );
function query_filter_assembly_steps_by_bunkie( $query ) {
    global $pagenow;
    // Get the post type
    $post_type = isset( $_GET['post_type'] ) ? $_GET['post_type'] : '';
    if ( is_admin() && $pagenow === 'edit.php' && $post_type === 'assembly_step' && isset( $_GET['bunkie_id'] ) && $_GET['bunkie_id'] !== 'all' ) {
        $query->query_vars['meta_key'] = 'bunkies';
        $query->query_vars['meta_value'] = $_GET['bunkie_id'];
        $query->query_vars['meta_compare'] = '=';
    }
}

I would really appreciate it if someone could show me how to make this work.
Thanks !