How can I get my part of ex-spouse pension after seven years?

I have talked to an Attorney about an omission of assets from my divorce I filed in 2007? Finalized in 2009. He said there would be no problem. He figured it to be an easy case. The decree states, there are no assets, period. I forgot about it. He was very abusive, my ex. I do need this to happen. The attorney said five hundred dollars, a d twenty-five dollars for a filing fee. I am on disability and need an Attorney that I can make payments to after the fact, or pro bono. I cannot come up with the money before hand. I'll make payments, no problem. His 62nd b-day is Nov. 22, 2016. I don't know when he will file, or d does it matter? Culinary union pension. He can only take half out in cash, rest in payments. Please help. Thanks,