Microsoft Exchange Account: how to configure public folder access?

I am searching for a way to access a public folder of my microscoft exchange account, more specifically I would like to use a shared calender that was setup by the means of a public folder.

In MacOSx the Calendar.app has a tab in the preference dialog to configure "Delegates" when trying to add an entry it seems only to look for users and not public/shared folders.

So after a long search I found Fantastical2.app, there I can configure such an access under Accounts in the preference dialog via the "Public Folder" button... and it works. I would have liked to keep the Calendar.app, but since this alternative is similar in look and feel, I am fine with it (a bit pricy though).

Now the remaining problem for me is that on my phone I still have not found a solution for it. Fantastical.app for iOS does not support that feature.

I searched for quite some time, and there was nothing I got to work. All I figured out so far was that ms-exchange accounts seem to cause all kind of trouble with Apple products. Meanwhile I ask myself what is so hard about synchronizing a calendar in this "cloudy" age we live in...

Any help on how to solve this would be appreciated.