Troubleshoot UnknownResourceException when following AWS tutorial

I'm attempting to follow this AWS tutorial. But I'm having trouble at "You can run GreeterWorker successfully at this point." as I'm getting an UnknownResourceException.

Exception in thread "main" com.amazonaws.services.simpleworkflow.model.UnknownResourceException: Unknown domain: helloWorldWalkthrough (Service: AmazonSimpleWorkflow; Status Code: 400; Error Code: UnknownResourceFault; Request ID: xxxxx)

Steps taken

• Resolved permission exception by attaching the SimpleWorkflowFullAccess IAM Policy to my AWS user.
• Verified that the helloWorldWalkthrough is registered on the SWF dashboard
• registered new helloWorldWalkthrough2 domain, same error occured

The tutorial didn't cover the step about attaching the SimpleWorkflowFullAccess policy to the AWS user, so I'm wondering if there is a similar undocumented step to allow my user to find this domain.

My code is copy/pasted from the GreeterWorker class in the tutorial.

import com.amazonaws.ClientConfiguration;
import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.services.simpleworkflow.AmazonSimpleWorkflow;
import com.amazonaws.services.simpleworkflow.AmazonSimpleWorkflowClient;
import com.amazonaws.services.simpleworkflow.flow.ActivityWorker;
import com.amazonaws.services.simpleworkflow.flow.WorkflowWorker;

public class GreeterWorker  {
   public static void main(String[] args) throws Exception {
     ClientConfiguration config = new ClientConfiguration().withSocketTimeout(70*1000);

     String swfAccessId = System.getenv("AWS_ACCESS_KEY_ID");
     String swfSecretKey = System.getenv("AWS_SECRET_KEY");
     AWSCredentials awsCredentials = new BasicAWSCredentials(swfAccessId, swfSecretKey);

     AmazonSimpleWorkflow service = new AmazonSimpleWorkflowClient(awsCredentials, config);
     service.setEndpoint("http://ift.tt/1KDc82N");

     String domain = "helloWorldWalkthrough";
     String taskListToPoll = "HelloWorldList";

     ActivityWorker aw = new ActivityWorker(service, domain, taskListToPoll);
     aw.addActivitiesImplementation(new GreeterActivitiesImpl());
     aw.start();

     WorkflowWorker wfw = new WorkflowWorker(service, domain, taskListToPoll);
     wfw.addWorkflowImplementationType(GreeterWorkflowImpl.class);
     wfw.start();
   }
}