checkboxes are not showing up on my rendered page ASP.NET

I have a asp.net C# page that is not rendering any check boxes that i am coding in to my page. I am not much of a CSS expert, but was hoping that somebody could point me in the right direction of things to check in my solution to figure out why my checkboxes are getting masked.

This is the code i'm working with:

<div id="Total" class="col s12">
                                    <p class="right-align small">
                                        <asp:PlaceHolder ID="DBTotalCount2" runat="server"></asp:PlaceHolder> 
                                        <!--# of Resuslts with max limit 50 shown--></p>
                                    <table class="striped as-table-outlined">
                                        <thead>
                                        <tr>
                                            <th>
                                                Name
                                            </th>
                                            <th>
                                                Email Address
                                            </th>
                                            <th>
                                                ID
                                            </th>
                                            <th>
                                                Date of Birth
                                            </th>
                                            <th>
                                                <asp:ImageButton id="imgSelectAllEmailsTotal" runat="server" ImageUrl="~/assets/img/icons_mail.gif" Enabled="False"  />
                                                <asp:CheckBox ID="chkSelectAllEmailsTotal" runat="server" OnCheckedChanged="chkSelectAllEmailsTotal_CheckedChanged"/>
                                            </th>
                                        </tr>
                                        </thead>
                                        <tbody>
                                        <asp:PlaceHolder ID="DBTotal" runat="server"></asp:PlaceHolder>  
                                        </tbody>
                                    </table>
                                    <table cellpadding="0" cellspacing="0" border="0" width="100%">
                                        <tr>
                                            <td class="auto-style1">
                                                <asp:Button ID="btnEmailSelectedTotal" runat="server" Enabled="true" Text="Email Selected Members" OnClick="btnEmailSelectedTotal_Click"/>                                               
                                            </td>
                                        </tr>
                                    </table><br/>
                                    <!--Pagination-->
                                    <ul class="pagination mt20">
                                        <asp:PlaceHolder ID="TotalPagination" runat="server"></asp:PlaceHolder>
                                    </ul>
                                </div>

The checkbox control chkSelectAllEmailsTotal shows up in the running source:

<th>
                                                <input type="image" name="ctl00$maincontent1$imgSelectAllEmailsTotal" id="maincontent1_imgSelectAllEmailsTotal" disabled="disabled" class="aspNetDisabled" src="../assets/img/icons_mail.gif">
                                                <input id="maincontent1_chkSelectAllEmailsTotal" type="checkbox" name="ctl00$maincontent1$chkSelectAllEmailsTotal">
                                            </th>

however on the page render it is not showing up at all. Inspect doesn't even show a hidden check box when i hover over the tag.

I would not know what css to locate or post that would be of help. What i'm hoping for is some direction on how i can debug this issue given the code above.

Hopefully this is an easy fix. Much appreciated for any help here!