What version of JBoss AS are you using and what JVM version is running it?
JBoss AS 7.1.1.Final "Brontes" on a Java 1.6 JDK (I'm using the embedded HornetQ module in /jboss/../modules/org/hornet)
I think the name of the MBean would be different in AS 7.1.1. The name "jboss.as:subsystem=messaging,hornetq-server=default,jms-queue=testQueue" looks like the old style name from previous versions of JBoss AS. If you connect to the JVM where JBoss AS is running with JConsole and look at the MBeans do you see any related to HornetQ?
With JConsole, I can see jboss.as:subsystem=messaging,hornetq-server=default,jms-queue=testQueue, so this seems right.
I've also tried
ObjectName queueObjectName = ObjectNameBuilder.DEFAULT.getJMSQueueObjectName(queue.getQueueName());
QueueControl queueControl = (QueueControl)MBeanServerInvocationHandler.newProxyInstance(server,queueObjectName,QueueControl.class,false);
And this returned
2014-05-05 16:06:39,815 ERROR [stderr] javax.management.InstanceNotFoundException: org.hornetq:module=JMS,type=Queue,name="testQueue"
I've tried to call the methods from JConsole. There is no error (so it only works remotely, not locally?), but the values are "wrong" (message counter is always 0, listMessages(AsJSON) is always empty, etc.)
I'm not sure what the problem could be. Can you try on WildFly or provide a reproducible test-case?