Export imported Exchange calendar as calDAV

Hey there,
I have integrated my Exchange (onpremise) calendar into nextcloud. Works perfectly so far.

I also export all calendars within nextcloud to another program via caldav. Now I have the problem that all native nextcloud calendars appear in the caldav link without any problems. However, the imported Exchange calendar does not.

And that even though the Exchange calendar also has a “Copy private link” option?

grafik

Is it a Bug that the Exchange Calendar is not exported through caldav or is the presence of the “copy private link” the Bug?

Hope someone can give me some insight into this.

thx, bye from Austria
Andreas