Moderating an entity that uses a special language (e.g. LANGCODE_NOT_SPECIFIED) throws exception

This was marked fixed, but we still get an exception being thrown. I have a node that is not set to be translatable, which gets 'zxx" as a language when it is created (through a migration process). This causes an exception being thrown inside EntityOperations::updateOrCreateFromEntity at the point when the translation is being added to the $content_moderation_state entity.

if ($entity->getEntityType()->hasKey('langcode')) {
      $entity_langcode = $entity->language()->getId();
      if (!$content_moderation_state->hasTranslation($entity_langcode)) {
        $content_moderation_state->addTranslation($entity_langcode);
      }
      if ($content_moderation_state->language()->getId() !== $entity_langcode) {
        $content_moderation_state = $content_moderation_state->getTranslation($entity_langcode);
      }
    }

Debugging this, I see that the $content_moderation_state entity has its language set to 'en' (site default), which is why the $content_moderation_state->hasTranslation($entity_langcode) fails ($entity_langcode='zxx').

Should we add extra checks here? or is the problem more that the $content_moderation_state doens't have it's language code set to 'zxx' (like the non-translated entity) ??