asp:HiddenField.Value is inaccessable *only* in I.E.?

Question

So, I have a nested telerik:RadGrid with an asp:HiddenField in it's Template column.

<telerik:RadGrid ID="rgStoreItems" runat="server" DataSourceID="dsStoreItems" CellSpacing="-1" GridLines="Both" OnItemCommand="rgStoreItems_ItemCommand">
    <MasterTableView DataSourceID="dsStoreItems" AutoGenerateColumns="True" DataKeyNames="StoreID">
        <Columns>
            <telerik:GridEditCommandColumn></telerik:GridEditCommandColumn>
        </Columns>
        <EditFormSettings EditFormType="Template">
            <EditColumn UniqueName="EditCol1" FilterControlAltText="Filter EditCol1 column"></EditColumn>
            <FormTemplate>
                <div style="width: 100%; text-align: center">

                    <asp:HiddenField ID="hfrgStoreItemsSelID" Value='<%# Eval("StoreID") %>' runat="server" />

                    <telerik:RadGrid ID="rgCoats" runat="server" DataSource='<%# fnGetDataSourceForItems(Eval("StoreID")) %>' AutoGenerateColumns="False" OnDataBound="rgCoats_DataBound">
                        <MasterTableView>
                            <Columns>
                                <telerik:GridBoundColumn DataField="Column" HeaderText="Item ID" FilterControlAltText="Filter Column column" UniqueName="Column" >
                                    <ItemStyle Font-Bold="True" />
                                </telerik:GridBoundColumn>
                                <telerik:GridTemplateColumn HeaderText="Current Verbage" FilterControlAltText="Filter TemplateColumn column" UniqueName="TemplateColumn" >
                                    <ItemTemplate>
                                        <asp:HiddenField ID="hfStoreID" runat="server" Value='<%# Eval("StoreID") %>' />
                                        <asp:TextBox ID="tbItemName" runat="server" TextMode="MultiLine" Height="40px" Width="100%" Style="resize: vertical; min-width: 325px" Text='<%# Bind("ItemName") %>'></asp:TextBox>
                                    </ItemTemplate>
                                </telerik:GridTemplateColumn>
                                <telerik:GridTemplateColumn HeaderText="Previous Name" FilterControlAltText="Filter TemplateColumn1 column" UniqueName="TemplateColumn1" >
                                    <ItemTemplate>
                                        <asp:Label ID="lblPrevName" runat="server" Text='<%# Bind("PrevName") %>' ForeColor="Gray"></asp:Label>
                                    </ItemTemplate>
                                </telerik:GridTemplateColumn>
                            </Columns>
                        </MasterTableView>
                    </telerik:RadGrid>

My problem here is I simply cannot access it's value (or really any other HiddenField on the pages' values). I've set a breakpoint on numerous areas where Hiddenfields are being used in the code, ran this page in Chrome, Firefox and Internet Explorer: Chrome and Firefox had zero issues and the values were reachable, Internet Explorer returned a blank value regardless of where it is in the code.

Any tips, work-arounds or points in the right direction would be greatly appreciated.