Update - the saga of the misdirected bag concluded yesterday with my partner picking up her bag at CDG. It had been one week since the bag missed her Air France flight from DUB to CDG and embarked on a journey across the pond and back. But now, it's sitting with us here in Paris.

Some key points come to mind:

1 - Having an Air tag in the bag was fortuitous as we knew it was in New York when we had actually received an email saying that it was being delivered to us in Paris.
2 - Following the Air France representatives's instruction to have the bag delivery in New York refused was key. If the bag had been delivered, AF would have been able to wash their hands of responsibility and we would have had to either A) arrange for shipping it back or B) do a MR back to NYC to retrieve it from the apartment (as we're staying for 5 weeks and have meetings to attend).
3 - Patience is a virtue - and defensive packing is a must. Some of her items were in my luggage which helped her get through some of her client meetings (albeit, she did have to purchase replacement items).

Two keep things contributed to this fiasco. The first, undoubtably, was Air France putting the bag on a flight to New York without first confirming with her that is what was to be done (recap: we flew NYC->CDG on Delta and have a return flight in July). The second, was the inability for Air France US to see Air France FR's baggage status (this certainly would have helped the representatives). It also, would have been nice to have a phone number of the Air France baggage handling department in New York to work with so that it didn't get dispatched to our home.

I appreciate everyone's response to my original post (admittedly written whilst sleep deprived and stressed out). Thank you.