The problem is that the radios are hidden, only the flat buttons are there.
The validator tries to get the position of the hidden input and fails with an error: jquery.validationEngine.js:1507 Uncaught TypeError: Cannot read property 'left' of undefined on line 1507
When you remove the display:none
.radio.btn-group input[type=radio] {
/* display: none; */
}
the red alert will show up.
So, that validation works. It is only the alert which fails with a javascript
edit; remove display:none and replace with opacity:0;