If you have evidence that your wife never stayed with you after the registered marriage (as you have mentioned that she has herself admitted in the FIR), then the case under Section 498-A IPC would be very weak. I hope by registered marriage, you mean the marriage performed before the Registrar under the Special Marriage Act.
Secondly, the allegations of demand of dowry that you have mentioned in your question, would require legal provisions of Dowry Prohibition Act, and they would not be covered under Section 498-A IPC.
Thirdly, legally speaking, if the registered marriage is legally valid, then there is no legal necessity of a further so-called social marriage. That is only for the satisfaction of the family members of relatives. Law fully recognizes the registered marriage. In this context, the dowry demand may lose some of its importance under the law.
You may consult some local lawyer by sharing full details with him (including relevant papers), and if so advised, you can try for quashing of FIR through the High Court.
Dr. Ashok Dhamija is a New Delhi based Supreme Court Advocate and author of law books. Read more about him by clicking here. List of his Forum Replies. List of his other articles. List of his Quora Answers. List of his YouTube Videos.