As you noted in your other thread, which has now been Closed due to violation of FT's cross-posting rules, the connection now violates DL's MCT. Whether that is an error and whether other carriers sell the connection is irrelevant. Similarly, because you booked through Expedia, it falls to Expedia to reissue the tickets.
If DL says that the tickets can be reissued and Expedia says that it cannot due to MCT, do a three-way call so that the factual issue is resolved. If indeed this is a DL MCT issue and the tickets can be reissued under an AF codeshare, ask Expedia to do that. If this cannot be resolved, you face the question of next best alternative and then dealing with Expedia and travel insurance after the fact. Only you know what the priorities are. Bear in mind that Expedia people are trained, even at more senior levels, to simply default to the next flight or whatever. Creative solutions such as reissuing under an AF codeshare to beat the MCT is not part of their thinking. Do bear in mind that while the short MCT is a potential solution and you will be rebooked in you misconnect, it is still somewhat suboptimal in terms of result.
For the sake of others, the lure of savings continues to lead people to book through third-party opaque vendors. They are great when it all works. When things go wrong, you are stuck with them. If booked through DL, DL would have fixed this in minutes and it would have been back when it occurred.