Получить внешний код свойства по его значению в Битрикс

$highLoadBlock = HighloadBlockTable::getList([
        'filter' => ['=TABLE_NAME' => "b_hlbd_proizvoditeli"]
    ])->fetch();
 
    $entity = HighloadBlockTable::compileEntity($highLoadBlock);
    $vendorClass = $entity->getDataClass();
 
    $dbVendors = $vendorClass::getList([
        "filter" => [
            "UF_NAME" => $_GET['brand']
        ]
    ]);
 
    $vendors = [];
    while ($vendor = $dbVendors->fetch()) {
        $arResult['MANUFACTURERS_CHECKED'][] = $vendor['UF_XML_ID'];
    }