@canuckchic we are in the same boat as you. We were DQ on March 11th, and we did not receive our interview letter. I've spoken to NVC twice (including a supervisor) and they said nothing is wrong; we are still waiting in the queue and they refused to investigate. I sent an email to the US Embassy in Montreal and they at least said they will investigate. I've also contacted my US Senator and I am waiting for them to respond. So incredibly frustrating and heartbreaking!
If anyone would be willing to assist us in the same way, it would be greatly appreciated.