All events except page_load not fired in dynamically loaded user control

See more:

ASP.NET

controls

event-handler

, +

I have a user control MembersFoundControl.ascx that is loaded into the MembersControl.ascx when duplicate members are found. The MembersFoundControl control definition is:

<%@ Control Language="C#" AutoEventWireUp="true" CodeBehind="MembersFoundControl.ascx.cs" Inherits="MemberTrack2016.ControlClasses.MembersFoundControl" %>

It is registered in MembersControl as:

<%@ Register Src="~/ControlClasses/MembersFoundControl.ascx" TagPrefix="mfctrl" TagName="MembersFoundControl" %>

It is loaded into a placeholder in the MembersControl as

MembersFoundControl memberListControl = LoadControl("~/ControlClasses/MembersFoundControl.ascx") as MembersFoundControl;
MembersFoundPlaceholder.Controls.Add(memberListControl);

the control events are defined in the MembersFoundControl as:

<div id="MemberListActionDiv" class="ButtonDivStyle" style="width: 36em; padding-top: 1em; padding-bottom: 0.5em">
        <asp:button id="UseNewMemberButon" cssclass="MemberButtonStyleLarge" text="Use New Member" runat="server" onclick="OnUseNewMember">
        <asp:button id="MFC_CancelButton" cssclass="MemberButtonStyle" text="Cancel" runat="server" onclick="OnMFCCancel" style="margin-left: .625em">
    </div>

And the Event operations are in the MembersFoundControl.ascx.cs file

protected void OnUseNewMember(object sender, EventArgs e)
        {
            MembersFoundEventArgs args = new MembersFoundEventArgs();
            args.nRetType = IDUSENEWMEMBER;
            args.MemberRec = null;
            args.nRelation = nRelationType;
            onUseThisMember(this, args);
        }

        protected void OnMFCCancel(object sender, EventArgs e)
        {
            MembersFoundEventArgs args = new MembersFoundEventArgs();
            args.nRetType = IDCANCEL;
            args.MemberRec = null;
            args.nRelation = nRelationType;
            onUseThisMember(this, args);
        }

When the control is loaded in the place holder the buttons are named and given the ids as follows:

<div id="MemberListActionDiv" class="ButtonDivStyle" style="width: 36em; padding-top: 1em; padding-bottom: 0.5em"></div>

The event is not fired in either MembersFoundControl or in MembersControl.

This is built in Visual Studio 2017 (2019 has problems).

Does anyone have any suggestions? THANKS

What I have tried:

I have tried everything I can think of.