Yes, there are only 3-4 TGVs a day to this destination (Nimes/Montpellier) without the hassle of having to go into Paris and navigate from Gard du Nord to Gard du Lyon. Somethings you just don't want to face with aged parents! And the next one is expensive and the one after that gets south pretty late.
So we are now arriving on the Friday night, overnighting at CDG and then going onwards

thanks for the help and confirming what I thought