I'm afraid I'm thoroughly confused as well.
If your had a lawyer submit your application, I would expect they would have handled all of this for you? And that your passport will be returned to their office and you will collect it from them.
You should not still physically be holding your passport unless you paid an extra £1,200 or so for the privilege. You definitely need to send your passport to NY if you did not pay for the Gold Settlement Service. For the Gold service, you would have attended your biometrics appointment in Atlanta, Boston, Chicago, Houston, LA, Miami, NYC, San Francisco, Seattle, or Washington DC.