Subscribe to Calendar

I used placeholders on the individual event page template to allow someone to add a specific event to their google & ical calendars. The placeholders work great – no problems there.

I also want to add a subscribe button to the main calendar page that allows someone to subscribe to the entire calendar which, from what I understand, is not native to the plugin. I found this thread useful: https://wordpress.org/support/topic/ical-feed-button-for-the-tech-newbs/ but while it does seem to add the feed url to my google calendar list, it doesn’t pull in any events.

Is this (below) all I have to add to the calendar page for it to work (assuming I change the url to my site’s feed url)? Am I missing a step from that thread?
Click here to add our calendar to your Google Calendar.

Any help would be highly appreciated. Thanks!