Did you include affidavits explaining your financial hardship? If you receive means tested benefits, and if you followed the instructions at http://www.uscis.gov/forms/tips-filing-form-i-912-request-fee-waiver, you have a good chance to get approved.
This answer is for informational purposes only and should not be construed as legal advice.
The I-912 for anyone with means tested benefit is made solely on that proof. USCIS has provided a memo to guide those filing the I-912. The other two options are discretionary and subject to USCIS determining whether the applicant deserves the waiver.
Legal disclaimer: The statement above is provided by CC Abbott is based on general assistance and not intended to be a legal opinion because not all the facts are provided. The person requesting information and all others reading the answer should retain an attorney who is permitted by the state bar within the jurisdiction who can examine the complete facts and provide a legal opinion on your case. All information provided in the above answer and other information provided by CC Abbott does not create an attorney/client relationship within any state of Federal law.