Like I had mentioned in your other thread, processing on your TRV application will begin only after your Voluntary Renunciation is approved.
Nonetheless, you must send both emails (to the CHD and ND visa offices) + Case Specific Enquiries to both these visa offices stating you had inadvertently misunderstood the question about previous visa refusals + give the details of your UK visa refusal + state you are declaring this UK visa refusal on your own without IRCC asking you for this information.
Do send these emails and CSEs asap