You have the right to remain silent. Anything you say can and will be used against you in a court of law. You have the right to talk to a lawyer for advice before we ask you any questions. You have the right to have a lawyer with you during questioning. If you cannot afford a lawyer, one will be appointed for you before any questioning if you wish. If you decide to answer questions now without a lawyer present, you have the right to stop answering at any time.
Seems pretty clear to me. Not a nickname. All silence after that point is perfectly warranted and should not be held against them. They can ask all the questions they want but they're not entitled to answers.