I'm booked on what was a very affordable Delta One fare ATL-FRA-ATL in late July. Because of the restrictions in Germany, I want to pivot to Croatia. KLM is the only Skyteam partner who can take me to Dubrovnik, and even that's with a connection.

If I book with another airline FRA-DBV-FRA, will I be allowed to claim my bags/change terminals/etc? I'm fully vaccinated but given the intense restrictions, I wasn't sure if this could be accomplished.

Any other ideas are welcome, too.

Thank you.