It is the published MCT (Minimum Connection Time) list for CDG Airport. Taken from ExpertFlyer.
However as I said your only option is an overnight, and UA will not provide accommodation.
I called again and they told me it was a "married connection". She claimed the gates would be either next to one another or very close and I would have "ample time". She also claimed that if I did miss the flight for whatever reason, United would put me on the next flight from Paris to DC (I did forget to ask when the next flight would be, could very well be the next day)