I do have experience with this type of scenario, having award tickets on BA and BA canceling its flights on one leg before departure (this was outbound Seattle-London, return Dublin-London-Seattle; BA decided to no longer fly Dublin-London). AS was unable to get BA to book us on another carrier, and BA directly was unhelpful. We had to find our way back from Dublin to London on our own to catch our BA flight, and wound up purchasing those tickets on a discount carrier. There were no other options on partner airlines.

So it's not a great situation for the OP. We had a marginally acceptable business class award experience on Condor six months ago. Among other smaller annoyances and challenges, it included something happening to our return tickets from Frankfurt to Seattle that required last-minute work at the airport counter in Frankfurt by a Condor rep to make them valid for travel. She originally didn't see our tickets in her system. Which was odd, because the outbound tickets were fine, and we were given no explanation of what the problem was on the return. Condor is marginal as a scheduled airline, overall.