Help with Unity and Kinect Voice Recognition - 'Microsoft.Kinect.SkeletonStream' Error

Hello, I am working on trying to implement voice recognition into a game using Kinect. As far as I have seen, the only way to do this is by using plugins. Is this true? I have been trying to write a C# script based off of this Kinect SDK example. I am using the free version of Unity. Here is what I have:

 using UnityEngine;
 using System;
 using System.Collections;
 using System.IO;
 using System.Linq;
 using Microsoft.Kinect;
 using Microsoft.Speech.AudioFormat;
 using Microsoft.Speech.Recognition;
 
 public class VoiceRecognition : MonoBehaviour {
     
     
     
     private SpeechRecognitionEngine speechRecognizer;
 //    public KinectSensor CurrentSensor; 
     
 
     
     private static RecognizerInfo GetKinectRecognizer()
     {
         foreach (RecognizerInfo recognizer in SpeechRecognitionEngine.InstalledRecognizers())
         {
             string value;
             recognizer.AdditionalInfo.TryGetValue("Kinect", out value);
             if ("True".Equals(value, StringComparison.OrdinalIgnoreCase) && "en-US".Equals(recognizer.Culture.Name, StringComparison.OrdinalIgnoreCase))
             {
                 return recognizer;
             }
         }
         
         return null;
     }
     
     
 
     private SpeechRecognitionEngine CreateSpeechRecognizer() {
         RecognizerInfo ri = GetKinectRecognizer();
         
         SpeechRecognitionEngine sre;
         sre = new SpeechRecognitionEngine(ri.Id);
         
         var grammar = new Choices();
         grammar.Add("hello");
         grammar.Add("goodbye");
         
         var gb = new GrammarBuilder{Culture = ri.Culture};
         gb.Append(grammar);    
         
         var g = new Grammar(gb);
         sre.LoadGrammar(g);
         
         sre.SpeechRecognized += SpeechRecognized;
         sre.SpeechHypothesized += SpeechHypothesized;
         sre.SpeechRecognitionRejected += SpeechRejected;
         
         return sre;
     } 
     
     private void SpeechRecognized (object sender, SpeechRecognizedEventArgs e)
     {
         if (e.Result.Confidence < .4)
         {
             RejectSpeech(e.Result);
         }
         
         switch (e.Result.Text.ToUpperInvariant())
         {
         case "HELLO":
             Debug.Log("Hi there.");
             break;
         case "GOODBYE":
             Debug.Log("Goodbye then.");
             break;
         default:
             break;
         }
     }
     
     private void SpeechHypothesized (object sender, SpeechHypothesizedEventArgs e)
     {
         Debug.Log("Hypothesized: " + e.Result.Text + " " + e.Result.Confidence);
     }    
     
     private void SpeechRejected (object sender, SpeechRecognitionRejectedEventArgs e)
     {
         RejectSpeech(e.Result);
     }
     
     private void RejectSpeech(RecognitionResult result)
     {
         Debug.Log("Excuse Me?");
     }
     
     
     
     
 /*    private KinectSensor InitializeKinect()
     {
         CurrentSensor = KinectSensor.KinectSensors.FirstOrDefault(s    => s.Status == KinectStatus.Connected);
         speechRecognizer = CreateSpeechRecognizer();
         CurrentSensor.Start();
         Start ();
         return CurrentSensor;
     }
 
 
     public VoiceRecognition() {
          InitializeKinect();    
     }    
 */    
     void Start () {
 
         
 /*    var audioSource = CurrentSensor.AudioSource;
         audioSource.BeamAngleMode = BeamAngleMode.Adaptive;
         var kinectStream = audioSource.Start();
         speechRecognizer.SetInputToAudioStream(kinectStream, new SpeechAudioFormatInfo(EncodingFormat.Pcm, 16000, 16,1,32000,2,null));
         speechRecognizer.RecognizeAsync(RecognizeMode.Multiple);
         CurrentSensor.AudioSource.EchoCancellationMode = EchoCancellationMode.None;
         CurrentSensor.AudioSource.AutomaticGainControlEnabled = false;
     */
         
     }
     
 
     void Update () {
     
     }
 }

I get no comilation errors until I add the commented code. I have already referenced the Microsoft.Kinect and Microsoft.Speech dlls, so I'm not sure what the problem is. The error I get is:

Internal compiler error. See the console log for more information. output was: Unhandled Exception: System.TypeLoadException: Could not load type 'Microsoft.Kinect.SkeletonStream' from assembly 'Microsoft.Kinect, Version=1.7.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.

at (wrapper managed-to-native) System.Reflection.MonoMethodInfo:get_method_info (intptr,System.Reflection.MonoMethodInfo&)

at System.Reflection.MonoMethodInfo.GetMethodInfo (IntPtr handle) [0x00000] in :0

at System.Reflection.MonoMethodInfo.GetAttributes (IntPtr handle) [0x00000] in :0

at System.Reflection.MonoMethod.get_Attributes () [0x00000] in :0

Any ideas would be great. Thanks.