make a URLRequest to an external server

I am having an awful time trying to figure out why I am getting Sandbox Security errors when making a request from our game host server to our gamesparks server.

trying to ask gamesparks for a method we made for user name generation

private const GET_NAMES:String = "https://E300018ZDdAx.preview.gamesparks.net/callback/E300018ZDdAx/generateName/YR5w9F53GYeMsP8LTBqijeeAsPM66v7J";

private function getNames():void

{

var postVars:URLVariables = new URLVariables();

postVars.count = 10

var req:URLRequest = new URLRequest(GET_NAMES);

req.method = URLRequestMethod.POST;

req.data = postVars;

var loader:URLLoader = new URLLoader(req);

loader.dataFormat=URLLoaderDataFormat.VARIABLES;

loader.addEventListener(Event.COMPLETE,check);

loader.addEventListener(IOErrorEvent.IO_ERROR, onError);

loader.addEventListener(SecurityErrorEvent.SECURITY_ERROR, onSecurityError);

loader.load(req);

}

protected function onSecurityError(event:SecurityErrorEvent):void

{

shellApi.logWWW(event.errorID, event.text);

removeEventHandling(event.target as URLLoader);

}

protected function onError(event:IOErrorEvent):void

{

shellApi.logWWW(event.errorID, event.text);

removeEventHandling(event.target as URLLoader);

}

protected function check(event:Event):void

{

trace(event.data);

removeEventHandling(event.target as URLLoader);

}

private function removeEventHandling(loader:URLLoader):void

{

loader.removeEventListener(Event.COMPLETE, check);

loader.removeEventListener(IOErrorEvent.IO_ERROR, onError);

loader.removeEventListener(SecurityErrorEvent.SECURITY_ERROR, onSecurityError);

}

in my searches everything people keep saying its due to our crossdomain.xml, but the game sparks crossdomain.xml we have seems pretty open

https://e300018zddax.preview.gamesparks.net/crossdomain.xml

<cross-domain-policy>

</cross-domain-policy>

they also say stuff like Security.loadPolicyFile(url);, but from what i understand that is only useful if the code is contained in the swf that is on the external game sparks server, but the request i am making is not to load a swf, but to get a json string from gamesparks.

I really don't have a good server background, so assume I know nothing and i am making this up as i go along, because i am.

thanks in advance.