Child JSON object undefined when its not - asp.net-mvc

Question

I have an array of JSON objects in the page source that all work except a child object (category).
Here is the code in cshtml:
<script type="text/javascript">
var initialData = #Html.Raw(Json.Encode(ViewBag.OfferItems));
</script>
Here is the resulting page source:
<script type="text/javascript">
var initialData = [{"Id":1,"Name":"Item1","ProductVariantLinks":[{"category":{"Id":2,"Name":"Basic Pizza","Products":null},"product":{"Id":1,"Name":"Margherita","Description":null,"ProductVariants":null},"productVariant":{"Id":1,"Name":"10 inch"}},{"category":{"Id":2,"Name":"Basic Pizza","Products":null},"product":{"Id":2,"Name":"Zeno","Description":null,"ProductVariants":null},"productVariant":{"Id":4,"Name":"8 inch"}}]},{"Id":2,"Name":"Item2","ProductVariantLinks":[]}];
</script>
As far as I can tell category is there and contains properties, but it appears as undefined in IE's debugger.
Is there something I'm missing?
P.S. the JSON is valid.
Update
I'm using knockoutjs and category is in inialdata until it does ko.applybindings. I'm not sure why it would do this, code below:
/// <reference path="jquery-1.5.1.js" />
/// <reference path="knockout-2.0.0.js" />
var ProductVariantLink = function() {
var self = this;
self.category = ko.observable();
self.product = ko.observable();
self.productVariant = ko.observable();
// Whenever the category changes, reset the product selection
self.category.subscribe(function() {
self.product(undefined);
self.productVariant(undefined);
});
};
var OfferItem = function() {
var self = this;
self.Name = new String();
self.ProductVariants = new Array();
};
var SpecialOfferItemModel = function (specialOfferItems) {
var self = this;
self.specialOfferItems = ko.observableArray(ko.utils.arrayMap(specialOfferItems, function (specialOfferItem) {
return { Id: specialOfferItem.Id, Name: specialOfferItem.Name, ProductVariants: ko.observableArray(specialOfferItem.ProductVariantLinks) };
}));
self.addSpecialOfferItem = function () {
self.specialOfferItems.push({
Id: "",
Name: "",
ProductVariants: ko.observableArray()
});
};
self.removeSpecialOfferItem = function (specialOfferItem) {
self.specialOfferItems.remove(specialOfferItem);
};
self.addProductVariant = function (specialOfferItem) {
specialOfferItem.ProductVariants.push(new ProductVariantLink());
};
self.removeProductVariant = function (ProductVariant) {
$.each(self.specialOfferItems(), function () { this.ProductVariants.remove(ProductVariant) })
};
self.save = function () {
var OfferItems = new Array();
$.each(self.specialOfferItems(),
function () {
var item = this;
var offer = new OfferItem();
offer.Name = item.Name;
$.each(item.ProductVariants(),
function () {
offer.ProductVariants.push(this.ProductVariant);
});
OfferItems.push(offer);
});
self.lastSavedJson(JSON.stringify(ko.toJS(self.specialOfferItems()), null, 2));
return false;
};
self.lastSavedJson = ko.observable("");
};
var model = new SpecialOfferItemModel(initialData);
ko.applyBindings(model);
$(function () {
$('#myForm').submit(function () {
model.save();
});
});
<table class="specialOfferItemsEditor">
<tr>
<th>
</th>
<th>
Name
</th>
<th>
ProductVariants
</th>
</tr>
<tbody data-bind="foreach: specialOfferItems">
<tr>
<td>
<div>
Delete</div>
</td>
<td>
<input data-bind="value: Name" />
</td>
<td>
<table>
<tr>
<th>
Category
</th>
<th>
Product
</th>
<th>
ProductVariant
</th>
</tr>
<tbody data-bind="foreach: ProductVariants">
<tr>
<td>
<select data-bind='options: ProductCategories, optionsText: "Name", optionsCaption: "Select...", value: category, uniqueName: true'>
</select>
</td>
<td data-bind="with: category">
<select data-bind='options: Products, optionsText: "Name", optionsCaption: "Select...", value: $parent.product, uniqueName: true' >
</select>
</td>
<td data-bind="with: product">
<select data-bind='options: ProductVariants, optionsText: "Name", optionsCaption: "Select...", value: $parent.ProductVariant, uniqueName: true'
>
</select>
</td>
<td>
<a href='#' data-bind='click: $root.removeProductVariant'>Delete</a>
</td>
</tr>
</tbody>
</table>
<a href='#' data-bind='click: $root.addProductVariant'>Add Product Variant</a>
</td>
</tr>
</tbody>
</table>

Answer 1

The JSON isn't coming in as you're expecting. I assigned the JSON string you provided above and my IE debugger was able to find 'category' without any issues.
Screenshot: https://i.stack.imgur.com/cI60U.jpg
Try to console.log (or alert) JSON.stringify(initialData);