Success
I was, yesterday, able to issue a stopover award for my mom: MCO-CVG-CDG; 1 week stopover; CDG-SOF (AF); SOF-CDG (AF)-PHL-ATL-MCO (all same day) for 60k miles in coach. The system auto-priced it at 85k miles (60k MCO-CDG-MCO and 25k CDG-SOF-CDG). The very helpful agent at the CVG call center had to involve: 1) her supervisor; 2) a SkyMiles supervisor; 3) the rate and reissue desk. Took about 1.5 hours on the phone.
What a nightmare! But I happened to stumble upon an EXCELLENT RES. AGENT @CVG RES.!!! It did help to put a human perspective to the story (mom is a school teacher, able to see different cities on the way to the home country; have been doing it for years, having done AMS/FCO/CDG/LHR in previous years).