Load external SWF loader content not accessible - actionscript-3

Question

Actually i have a SWF that is loaded by another SWF.
This SWF that is loaded, itself load another SWF.
This may be weird, but it's in a context of an online game that let you develop SWF as plugins.
So, we have SWFA(the video game) ---> SWFB ----> SWFC
When i try to load the external SWFC, the COMPLETE event fire, but i am only able to add it to the stage by adding directly the Loader, because the loader doesn't have any content property.
public function load(){
loader = new Loader();
loader.contentLoaderInfo.addEventListener(HTTPStatusEvent.HTTP_STATUS, httpStatusHandler);
loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onComplete);
loader.contentLoaderInfo.addEventListener(SecurityErrorEvent.SECURITY_ERROR, onSecurityError);
loader.contentLoaderInfo.addEventListener(IOErrorEvent.IO_ERROR, onIoError);
loader.contentLoaderInfo.addEventListener(IOErrorEvent.NETWORK_ERROR, onIoError);
loader.contentLoaderInfo.addEventListener(AsyncErrorEvent.ASYNC_ERROR, onAsyncError);
applicationContext = new LoaderContext(true, ApplicationDomain.currentDomain);
loader.load(getRequest(),applicationContext);
}
private function getRequest():URLRequest {
Security.allowDomain("https://mock.com");
Security.loadPolicyFile("https://mock.com/crossdomain.xml");
var req:URLRequest = new URLRequest("https://mock.com/mock.swf");
req.method = URLRequestMethod.POST;
req.data = new URLVariables("name=kk");
var encoder:Base64Encoder = new Base64Encoder();
encoder.encode("user:pass");
var credsHeader:URLRequestHeader = new
URLRequestHeader("Authorization", "Basic " + encoder.toString());
req.requestHeaders.push(credsHeader);
return req;
}
Here is the onComplete function
public function onComplete (e:Event):void{;
this.addChild(e.target.content); // this is null
this.addChild(e.currentTarget.content); // null too
}
So, when i run my SWF from my local computer, everything goes well, e.target.content contain my external SWF.
But when i run the same within the SWF Loader inside the online game, i can't find any content property. Plus, childAllowParent property of LoaderInfo is always false.
Does someone have an idea of what's going on?
Thanks