Get radio values from callback

Hi,
I'm creating a shipping method for Drupal Commerce Kickstarter. I've created a type of shipping method with a flat rate etc. but I want to create a search via a 'zipcode' where a user can enter a zipcode and get the results from the service via an XML response that I'm printing out as radio values. I am using an AJAX callback to replace the search form with a new radio input, but I can't get it to print out. All I can get to print out from the radio input is the description, nothing more. How can I print out the whole input?

Another thing: I tried getting the $form['postitoimipaikka'] to the callback with $form_state['values']['postitoimipaikka'], but for some reason it doesnt pass that value on either.

I am using a static search value to test this out. I also know the XML response is a funky one but it's the only method I got it to work.

/**
 * Shipping service callback: returns the example shipping service details form.
 */
function commerce_shipping_itella_service_details_form($pane_form, $pane_values, $checkout_pane, $order, $shipping_service) {
  $form = array();

  $form['postitoimipaikka'] = array(
    '#type' => 'textfield',
    '#title' => t('Postitoimipaikka'),
    '#description' => t('Syötä postitoimipaikkasi.'),
    '#default_value' => '',
    '#required' => TRUE,
  );

  $form["submit"] = array(
    "#type" => "submit",
    "#value" => "Search", 
    "#ajax" => array(
            "callback" => "commerce_shipping_itella_service_form_callback", 
            "wrapper" => "commerce-shipping-service-details",
            "effect" => "fade"
            )
    );

  return $form;
}

/**
 * Shipping service callback: increases the shipping line item's unit price if
 * express delivery was selected.
 */
function commerce_shipping_itella_service_form_callback($form, &$form_state) {
  $postitoimipaikat = array();

  // Replace Helsinki with a form_state
  $url = "https://ohjelmat.posti.fi/pup/v1/pickuppoints?zipname=Helsinki&top=3";

  $curl = curl_init();
  curl_setopt($curl, CURLOPT_URL, $url);
  curl_setopt($curl, CURLOPT_TIMEOUT, 130);
  curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
  $response = curl_exec($curl);
              curl_close($curl);

  $xml = json_decode($response, true);

  foreach($xml as $key => $value)
  {
     $postitoimipaikat[] = $value['PublicName'] . ", " . $value['PostCode'];
  }

  $form['postitoimipaikat'] = array(
    '#type' => 'radios',
    '#description' => t('Valitse toimipaikka, johon lähetys toimitetaan'),
    '#options' => $postitoimipaikat,
    '#required' => TRUE,
  );

  return $form['postitoimipaikat'];
}