How to download a file for specific users

Question

To download a file from a third-party website, I use code similar to that in the first section below. The token is necessary, and the download will not proceed if it is invalid. With my own site, I wish to replicate that action. Although I am in charge of both the transmitting and receiving servers, I am unable to make this function. Please tell me what I'm doing incorrectly.

The code on the sending server:

    $url = "https://example.com/download/index.php?token=$someid";

    $ch = curl_init($url); 
    curl_setopt($ch, CURLOPT_FILE, $fp); 
    curl_setopt($ch, CURLOPT_TIMEOUT, 20);  
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, '1'); 
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, '1');
    curl_exec($ch);

    try {
        if(curl_errno($ch)){
            throw new Exception(curl_error($ch));
        }
    }
    catch (Exception $e){ echo $e->getMessage(); } 

    $statusCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);  
    curl_close($ch);

    if ($statusCode == 200) {
      handle the downloaded file
    } else {
      echo 'Result = '. $statusCode; 
    }

And this is on my website (the receiving server). When I run the code above, I should get a 404 error, but all I get is "Result =" because the true is only there for testing.

    if (true || ! empty($_GET['token'])) {
        header("HTTP/1.1 404 Not Found");
        exit;
    } 
    header("Location: http://example.com/myfile.zip");
    exit; 

Can someone please help me with this?