Multiple Calendar notifications for same event

TL;DR: I am getting notifications for events on my co-workers calendars, but only if I am also invited to the same event. The result is multiple notification pop-ups for the same meeting, but only one of the pop-ups corresponds to my calendar. How do I make it stop?

Details:

My work email is hosted on Gmail, and everyone at our company also uses Google Calendar to schedule events.

While most of my colleagues use a browser window to review and schedule events on their calendar, I prefer to use macOS Calendar desktop app for reviewing. Scheduling from Apple Calendar does not seem to work well but that's ok since I don't often schedule meetings. I also use Apple Mail instead of accessing Gmail in a browser.

In order to see my Gcal events on my Apple Calendar I added my google account to my mac by going to "System Preferences > Internet Accounts", adding my google account and checking "Mail" and "Calendar".

Because I follow my co-workers' calendars in my google account, their calendars show up in the left side-bar of Apple Calendar, and their events show up in the calendar display next to events on my calendar. This part is helpful for me to see their availability. But because I don't need to be alerted about their events, I go to "Get Info" in the right-click menu of each calendar and check "Ignore Alerts", but I am still being notified for events on their calendars.

More specifically, I receive pop-up notifications to events on other people's calendars to which I am also invited. For example, today myself and 2 other colleagues were invited to a meeting, and I received 3 identical pop-ups, all of which include the "accept" and "decline" option, but only one of them is for my personal calendar. (Screenshot below)

Fortunately I have learned over time that I can click "accept" or "decline" on all three and only my personal Gcal will be affected but it is still a really annoying bug that I can't seem to figure out.

Any help would appreciated!

FWIW I have a 2019 MBP running Big Sur 11.6, which I keep up to date, and have experienced this issue as far back as macOS Sierra.