How to construct a webinar registration cancel hyperlink?

Hi all,

I’m using the Zoom API via PHP to automatically add a Webinar Registrant. This is working fine:

class AddWebinarRegistrantListener implements Listener
    public function handle(Event $event)
        if ('online' === $event->printer->booking_detail->type) {
            $zoom_helper = IoC::make('ZoomHelper');
            $registrant  = $this->createWebinarRegistrant($event->printer);
            $response    = $zoom_helper->addWebinarRegistrant(

            $event->printer->webinar = $this->storeZoomWebinarResponse($response);

In another listener class, I create a custom email notification for our visitor, because we don’t want to use the standard email that Zoom sends. For our custom email, I need to construct a “cancel registration” link. I’ve checked a few of the hyperlinks in the Zoom emails, and they all seem to have a different hashcode in the query string params. Is there any way to construct this cancel hyperlink myself?

Thanks in advance.