Changes to calendar events aren't syncing to TimeFinder

I had a repeating task in a Google calendar that I deleted (all events in the series). The event series no longer shows on my Apple Calendar on Mac. However, the events still show in TimeFinder. Because it was an event that repeated indefinitely, it’s going to be a bit painful if I have to delete every individual instance far into the future. I’m not sure if changes like this are meant to sync to TimeFinder, or if the calendar sync is a one-time import. I’ve tried turning sync off and back on but it doesn’t change.