Update job_item with hook_tmgmt_job_checkout_before_alter fails

Problem/Motivation

I want to prevent a field 'field_url_neu' from being translated, depending if the translated field exist and has already a value and a boolean field 'field_xliff_url_neu' is not true.

Steps to reproduce

Using the following code:

function hook_tmgmt_job_checkout_before_alter(&$remaining_jobs, &$jobs) {
  foreach ($jobs as $job) {
    $target_language = $job->getTargetLangcode();
    
    // set translate to false for field_url_neu, if value exists already in translation
    /** @var \Drupal\tmgmt\Data $data_service */
    $data_service = \Drupal::service('tmgmt.data');
    foreach ($job->getItems() as $job_item) {
      $unfiltered_data = $job_item->getData();

      $data = $job_item->getData(['field_url_neu']);

      if (isset($unfiltered_data['field_url_neu']) && $job_item->getItemType() == 'node') {
        $entity_id = $job_item->getItemId();
        $node = \Drupal::entityTypeManager()->getStorage('node')->load($entity_id);

        if ($node->hasTranslation($target_language)) {
          $translated_node = $node->getTranslation($target_language);

          if ($node->hasField('field_xliff_url_neu') && !$node->get('field_xliff_url_neu')->isEmpty() && $node->get('field_xliff_url_neu')->getValue()[0]['value'] == true) {
            \Drupal::messenger()->addMessage('Override URL in translations for node id: ' . $node->id());
          } elseif ($translated_node->hasField('field_url_neu') && !empty($translated_node->get('field_url_neu')->getValue())) {
            $data[0]['value']['#translate'] = false;
            $job_item->updateData(['field_url_neu'], $data, FALSE);
          }
        }
      }
    }
  }
}

Translate to several languages as a batch job.

Preventing the field 'field_url_neu' from being translated works for the first job/language and in all other the 'field_url_neu' is translated.

Do I'm missing something in the code or would it be better, to take another way for this functionality?