var tokenJson = JsonConvert.SerializeObject(tokenJsonString);

    var jsonResult = JsonConvert.DeserializeObject<Dictionary<string, dynamic>>(jsonString);
    var firstItem = jsonResult["data"][0];

"{"token":"1edd6006-678a-4e6a-ab65-4fa60efa8632"}"

Dim tokenJson = JsonConvert.SerializeObject(tokenJsonString)

 Dim jsonResult = JsonConvert.DeserializeObject(Of Dictionary(Of String, Object))(jsonString)
 Dim firstItem = jsonResult.Item("data").Item(0)

Dim firstItem = jsonResult.Item("data").Item(0).Value(Of String)("token")