How to fix runtime binder exception when trying to gettype of json property?

See more:

C#

JSON

deserialization

//Here is the Json

{
    "groups": null,
    "data": [{
            "type": 123,
            "name": "Name123"
        },
        {
            "type": 567,
            "name": "SecondName"

        }
    ],
    "total": 2

}

// I am then deserializing my json to either dictionary or list.. in this case it would be a List.. and then I am using a foreach loop to first get the Type..
result[t].GetType() gives me the exception

var result = Helpers.JsonHelper.DeserializeToDictionaryOrList(jsonString);

    foreach (var t in result.Keys)
                    {
                        var actualType = result[t].GetType();  

                    }

//Here the DeserializeToDictionaryOrList method for reference

public static class JsonHelper
   {
       public static dynamic DeserializeToDictionaryOrList(string jsonString, bool isArray = false)
       {
           if (!isArray)
               isArray = jsonString.Substring(0, 1) == "[";

           if (!isArray)
           {
               var responseJson = JsonConvert.DeserializeObject<Dictionary<string, object>>(jsonString);
               var copyOfResponseJson = new Dictionary<string, object>();
               foreach (KeyValuePair<string, object> myDictionary in responseJson)
               {
                   if (myDictionary.Value is JObject)
                       copyOfResponseJson.Add(myDictionary.Key, DeserializeToDictionaryOrList(myDictionary.Value.ToString()));
                   else if (myDictionary.Value is JArray)
                       copyOfResponseJson.Add(myDictionary.Key, DeserializeToDictionaryOrList(myDictionary.Value.ToString(), true));
                   else
                       copyOfResponseJson.Add(myDictionary.Key, myDictionary.Value);
               }
               return copyOfResponseJson;
           }
           else
           {
               var responseJson = JsonConvert.DeserializeObject<List<object>>(jsonString);
               var copyOfResponseJson = new List<object>();
               foreach (var myDictionary in responseJson)
               {
                   if (myDictionary is JObject)
                       copyOfResponseJson.Add(DeserializeToDictionaryOrList(myDictionary.ToString()));
                   else if (myDictionary is JArray)
                       copyOfResponseJson.Add(DeserializeToDictionaryOrList(myDictionary.ToString(), true));
                   else
                       copyOfResponseJson.Add(myDictionary);
               }
               return copyOfResponseJson;
           }
       }

What I have tried:

I am not sure why this is causing the exception.. it was just fine with another Json.. I am guessing because first time result[t] is groups and the value in the json is null.. I am not really sure about this..