Custom JS form submit in PopUp Pro

Having a devil of a time getting some custom javascript working in our popup. We use an ESP called Silverpop and we wrote some custom JS/PHP to handle opt-ins that works quite well. However, when we implement this code within a popup we can't get anything to fire at all - the popup just refreshes on submit using any of the available options on form submit.

Would you be able to provide an extra set of eyes on this for us? If you need access to the backend I just enabled support access.

Thanks a bunch.
Web Dev @ Boardroom, Inc.