PWC is NOTORIOUSLY bad in these situations. I know of many case where they have screwed people up royally, and know of a case where they were fired from a very large European company due to the screw-ups they made in expat taxes.

There IS a tax treaty between the US and France and it has existed for many years. This should have saved you from double taxation.

Hell, I once had a meeting with PWC where their "expert" declaed that I needed to submit a tax return from a country that has NO personal Tax Returns!!