MacOS Sequoia/Tahoe Calendar app not updating Exchange events - (Sorta Solved)

Hello everyone,

I posted this problem in July, but got no responses, other than a handful of thumps up and some experiencing the same thing. The post got closed, so here is a new one. This is still a bug, but at least for me, it's mostly resolved, and I've shared my resolution below.

Issue summary:

When I responded to Exchange calendar invitations via Mac Mail—whether Accept, Decline, or Maybe—the response correctly updated on the Exchange server, however, the Mac Calendar app did not reflect these updated RSVP statuses. Instead, events continued to show as accepted regardless of my actual response. Further, I could not delete those events. Refreshing calendars for the Exchange account did not correct this, nor did killing exchangesyncd. The only temporary fix I found was to disable and then re-enable the Exchange account in Internet Accounts, which forced a full resync—but this was inconvenient and not sustainable. Further, that solution didn't work in Tahoe.

What "worked":

It took a lot of trial and error to get here, but I noticed that I had logged in with one of the two variations of my Exchange email address (username@company.com) So I tried logging in with the other variation of my email address (first.last@company.com) and voila, the problem was solved.

However, this does not fully solve the problem because if anyone uses my other email address to send me an invitation, this problem creeps back in. So, hopefully an Apple person sees this and can resolve this "alias" issue. Doesn't seem to be a problem on iOS. And it wasn't a problem before Sequoia.