custom outside db connection (specific case)

function wpmu_form_ex_get_submissions( $order_id ) {

    $sub_count = array();
    // connect to external DB
    $edb_host = '';
    $edb_pass = '';
    $edb_user = '';
    $edb_dbname = '';

    $external_db = new wpdb( $edb_user, $edb_pass, $edb_dbname, $edb_host );


    // get max submissions allowed

    $results = $external_db->get_results( $external_db->prepare( "SELECT `Identity_Number_Totals` FROM `shop_donor_card_purchases` WHERE `Order_ID` = %s", $order_id ) );
    $sub_count['max'] = $results[0]->Identity_Number_Totals;

    // get current number of submissions

    $results = $external_db->get_results( $external_db->prepare( 'SELECT COUNT(`Order_ID`) AS `remain`  FROM `shop_donor_card_purchases_print` WHERE `Order_ID` = %s', $order_id ) );
    $sub_count['count'] = $results[0]->remain;


    // calculate remaining allowed submissions (max - existing)

    $sub_count['remaining'] = $sub_count['max'] - $sub_count['count'];

    // and return

    return $sub_count;

}

add_filter( 'forminator_render_form_markup', 'wpmu_form_ex_prerender', 10, 4);
function wpmu_form_ex_prerender( $html, $form_fields, $form_type, $form_settings ) {


    // execute only if specific form is displayed (replace number with your form ID

    if ($form_settings['form_id'] == '13660' ) {

        // get Order ID from URL (see commented out function at the bottom of this code)

        $order_id = get_query_var( 'order_id' );

        // get submissions (maximum allowed, number of made already and calculate remaining)

        $submission_count = wpmu_form_ex_get_submissions( $order_id );


        // create custom above the form messsage

        $my_header = '<div class="forminator_limit_info">
            <p>Your ORDER ID: '. $order_id . '</p>
            <p>Remaining submissions: ' . $submission_count['remaining'] . ' of ' . $submission_count['max'] . '</p>
            </div>';


        // if there are remaining submissions, output custom header info and form
        // otherwise "destroy" the form and output only custom header

        if ( $submission_count['remaining'] > 0 ) {
            $html = $my_header . $html;
        }
        else {
            $html = $my_header;
        }

    }

    return $html;

}

//if you don't see actual ORDER ID above the form but only the "Your Order ID:" message
// without actual ID, uncomment below code:

//function wpmu_form_ex_query_vars( $qvars ) {
 //   $qvars[] = 'DataProc';
  //  return $qvars;
//}
//add_filter( 'query_vars', 'wpmu_form_ex_query_vars' );