I'm still not sure why you are using a hand coded connection file, but your syntax is wrong.  The code:
  if (mysqli_errno()) {
    die('<p>Failed to connect to MySQL: '.mysqli_error().'</p>');
  } 
should be:
  if (mysqli_errno($conn1_i)) {
    die('<p>Failed to connect to MySQL: '.mysqli_error($conn1_i).'</p>');
  }


