NotOnServer only shows files if parent directory of missing file exists

I suspect the culprit might be this line in Drupal\auditfiles\Auditor\AuditFilesNotOnServer:

$target = $this->fileSystem->realpath($result->uri);

This is converting a URI found in the file_managed table to a realpath, but it appears to return false if the file parent directory doesn't exist when it needs to return the full path to the missing file.

For context, here's the entire method:

  public function getReferences(): \Generator {
    $maximumRecords = $this->auditFilesConfig->getReportOptionsMaximumRecords();
    $query = $this->connection->select('file_managed', 'fm');
    $query
      ->orderBy('changed', 'DESC')
      ->range(0, $maximumRecords)
      ->fields('fm', ['fid', 'uri']);
    /** @var array<object{uri: string, fid: string}> $results */
    $results = $query->execute()->fetchAll();
    foreach ($results as $result) {
      $target = $this->fileSystem->realpath($result->uri);
      if ($target !== FALSE && !file_exists($target)) {
        yield FileEntityReference::create((int) $result->fid);
      }
    }
  }

Ref: https://www.php.net/manual/en/function.realpath.php

Note:

The running script must have executable permissions on all directories in the hierarchy, otherwise realpath() will return false.

If a parent directory doesn't exist then realpath will return false, excluding it from this module's file_exists check and therefore not showing it in the "not on server report".