Call uscis again to find out from a diff operator. but it can take a few weeks too.
Dont ask how long it takes first. ask for a status update on the case and if they still got it over there then ask how long it will take.
instead of talking with the first human that answers the phone,
yer USCitizen petitioner should be talking with an ISO, a Tier 2 Human,
and try to ascertain
if the casefile is still sitting in the building at some USCIS office,
or if it was actually shipped out to NVC and if so, on what day.
As ISO can see more 'in the system' than the first human that answers the phone.
So, tell yer USCitizen Petitioner Human to call in again, and ask for an ISO, then find out exactly where the casefile is during that phone call.
Go Get Em, and Good Luck !