1) You have a redirect in your insert server behavior so the code to send the email doesn't have a chance to run. Move the redirect go to page to the email server behavior instead, or move the email code above the insert.
2) In your css file you have:
[type="checkbox"]:checked, [type="checkbox"]:not(:checked) {
position: absolute;
opacity: 0;
pointer-events: none;
}
That makes any checkboxes that aren't checked invisible. You would have to remove the opacity to fix that issue.