Apple Calendars and google calendars syncing inconstistantly

Since Sequioa, All the macs on my campus have had calendar inconsistant sycing issues. One day it will be fine and then next it won't sysnc. This was not an issue before sequioa.

I tested it on on high sierra and I have never had an issue. I now have also tested this on both sequioa and tahoe. I am able to recreate it. I have deleted and re-added the accounts, turned accounts on and off and changed DNS (its always DNS). I have checked with our network admin and we are not blocking anything that would interfere with. We have meraki environment

The funny thing is that if I subscribe to a google calendar the syncing is instant. If I add the account it The most common error I get is that is cannio connect to the server. I have been down all the rabbit holes and I have not seen anyting that helps. I will buy you a kitkat If you know the answer!!