WF Access the workflow instance variables from load and unload

SqlTrackingWorkflowInstance instance = null;
//wfServiceHost is an instance of WorkflowServiceHost
WorkflowRuntimeBehavior workflowRuntimeBehaviour = wfServiceHost.Description.Behaviors.Find<WorkflowRuntimeBehavior>();
WorkflowRuntime wfRuntime = workflowRuntimeBehaviour.WorkflowRuntime;

if (wfRuntime != null)
{
        SqlTrackingService trackingService = (SqlTrackingService)wfRuntime.GetService(typeof(SqlTrackingService));
        SqlTrackingQuery sqlTrackingQuery = new SqlTrackingQuery(trackingService.ConnectionString);

         sqlTrackingQuery.TryGetWorkflow(instanceId, out instance);
}

this.TrackData("name", myObject)

foreach (UserTrackingRecord userTrackingRecord in
    sqlTrackingWorkflowInstance.UserEvents)
{
    Console.WriteLine("Key : {0}  Data : {1}",
        userTrackingRecord.UserDataKey,
        userTrackingRecord.UserData.ToString());
    if (userTrackingRecord.UserDataKey == "Job")
    {
        OrderRequest request = userTrackingRecord.UserData as OrderRequest;
        if (request != null)
        {
            Console.WriteLine("nJob ID: {0}", request.JobID);
        }
    }
}