Case Tracker Basic: wrong hook_access

Maybe it is a wrong interpretation of my side, but, in this function:

/**
 * Implementation of hook_access().
 */
function casetracker_basic_case_access($op, $node) {
  global $user;

  switch ($op) {
    case 'view':
      // we have to check if the OG module is installed, otherwise this will
      // overule the OG nodeaccess
      if (!module_exists('og')) {
        return user_access('access case tracker');
      }
      // we check if the case isn't created by the current user or is
      // assigned to the current user, if so that user gets access
      elseif (
        user_access('access case tracker')
        && 0 < (int)$user->uid
        && ((int)$node->casetracker->assign_to === (int)$user->uid
           || (int)$node->uid === (int)$user->uid)
      ) {
        return TRUE;
      }
      break;
    case 'create':
      return user_access('create cases');
    case 'update':
    case 'delete':
      if (user_access('edit own cases') && ($user->uid == $node->uid)) {
        return TRUE;
      }
      break;
  }
}

This code:

if (!module_exists('og')) {

shouldn't be?

if (module_exists('og')) {

This is because, if a user didn't installed Organic Groups, Case Tracker Basic should restrict access based in 'assign_to' and 'author'

I'm wrong? or this is indeed a bug?

If this is a bug, I'm attaching the proper patch