Для тех, у кого предыдущий способ не сработал :)
function direct__GetReports($token, $login) {
    $params = array(
        'method' => "AccountManagement",
        'param'  => array(
            'Action'            => "Get",
            'SelectionCriteria' => array(
                'Logins' => array($login),
            ),
        ),
        'locale' => "ru",
        'token'  => $token,
    );
    $headers = array(
        'POST /json/v5/ads/ HTTP/1.1',
        'Host: api.direct.yandex.com',
        'Authorization: Bearer ' . $token,
        'Accept-Language: ru',
        'Client-Login:  ' . $login,
        'Content-Type: application/json; charset=utf-8',
    );
    $url = 'https://api.direct.yandex.ru/live/v4/json/';
    $ch  = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_POST, 1);
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($params));
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    $server_output = curl_exec($ch);
    curl_close($ch);
    return json_decode($server_output, true);
}