Post Not Returning Response

[GhstTracker]

I am having an issue where a post WebApi method is not returning a response to the consuming client.

The client is another controller in the same solution/website (for testing purposes)

When I remove the Authorize attribute from the Post method everything works as expected and I recieve the response from the post method.
Client Method calling the post method

        Dim postUri As String = "1/client/DataXChangeTester/type/CollisionReport"

        Dim leftChild As New QueryNode With {.NodeValue = "drivers.name.lastName"}
        Dim rightChild As New QueryNode With {.NodeValue = "McNear"}

        Dim simpleOperation As New QueryNode With {.NodeValue = "is",
                                                  .LeftNode = leftChild,
                                                   .RightNode = rightChild}

        Dim queryToSend As QueryDetails = New QueryDetails With {.QueryDetail = simpleOperation}

        TesterClient = New HttpClient(HawkClientHandler)
        'TesterClient = New HttpClient()
        Dim webAddress As String = ConfigurationManager.AppSettings("ServiceURL")
        TesterClient.BaseAddress = New Uri(webAddress)

        TesterClient.DefaultRequestHeaders.Accept.Add(New MediaTypeWithQualityHeaderValue("application/json"))

        Dim action = TesterClient.PostAsync(postUri, queryToSend, New JsonMediaTypeFormatter())

        '30 second timeout.
        action.Wait(30000)


        Dim response As HttpResponseMessage = action.Result

        If response.IsSuccessStatusCode Then
            ViewData("PredefinedQueryMessage") = response.Content.ReadAsStringAsync().Result
            Return View("Index")
        Else
            ViewData("PreDefinedQueryErrorMessage") = response.Content.ReadAsStringAsync().Result
            Return View("Index")
        End If

Client credential and message handler setup

 TestCredential = New HawkCredential With {
            .Id = "BuyCrashTN",
            .Algorithm = "sha256",
            .Key = "1531d118-ae19-11e3-b324-28cfe9215d9f"}

        HawkClientHandler = New HawkClientMessageHandler(New HttpClientHandler(), TestCredential)

Server side code

WEBApiConfig

 Dim handler As New HawkMessageHandler(New HttpControllerDispatcher(config),
                                              Function(credential)
                                                  Return Task.FromResult(RetrieveCredential(credential))
                                              End Function)

Post Method

 'POST 'api/1/client/ClientName/type/TypeName
    <Authorize>
    <AcceptVerbs("POST")>
    Public Function Query(requestMessage As HttpRequestMessage,
                          clientId As String,
                          typeName As String,
                          <FromBody> requestedQuery As QueryDetails) As HttpResponseMessage
        Dim responseContents As New QueryResults()
        Dim response As HttpResponseMessage
        Dim requestId As Integer = -1
        Try
            requestId = LogRequest("Received Query", requestedQuery)
            ReportType = GetType(DataXChangeCollisionQuery)
            Parameter = Expression.Parameter(ReportType, "report")
            responseContents = ExecuteQuery(requestedQuery)
            response = requestMessage.CreateResponse(HttpStatusCode.OK, responseContents)
        Catch ex As Exception
            response = requestMessage.CreateErrorResponse(HttpStatusCode.InternalServerError, "Error Processing Provided Query")
        End Try
        LogRequest("Exiting Query Operation", requestedQuery, requestId)

        Return response
    End Function