You’ve probably looked into this, but just in case not, you probably won’t be able to claim for the tickets on your insurance, as most insurers state it is the airlines responsibility to get you home. However annoying and orange .
This is correct. It IS the airline’s responsibility to get you home, EU regulations set the rules and mandate compensation levels too. My mum and dad had exactly this from the South of France a couple of years ago. Getting the tickets refunded, a nights hotel and the compensation was a real struggle, but she persisted and got it all back in the end.
If your journey doesn’t start in Paris, get the train to Lillie and on the Eurostar there was the recommendation from the SNCF staff. (That nugget of info probably too late now.)