Survivor benefits for my child with unproven paternity

My 6 year old sons father died last month, and I was told by someone in the ssi office that because paternity had not yet been proven (which we were in the process of working with child support at the time of his death to do so), and that because he had never signed any documents stating he was his father and was not named on the birth certificate that he is unable to get benefits... I was able to find one lawyer out of over 15 called that would even be willing to help, but am not able to afford to pay his expensive rates.. I have signed every document since my pregnancy listing him as the only possible father, and I have several people that know that his father and i lived together during the entire time, before and after, I bacame pregnant.. He also told his new wife, and his son whom he brought over to visit my child often, and him and his brother still talk on the phone.. Does anyone have any advice as to what I should do? I think I might take my chances and apply, I believe i just barely might have enough people's statements to satisy the fact that, yes, he is his father and there was no possible other father.. Does anyone know of any cases of unproven DNA paternity/undocumented admittance on his part like this being won?? or do I need to file all appropriate legal forms with the states court where he was residing at the time of his death.. My children and I moved 2 years ago out of state, so this complicates things even worse for me to do on my own.. Any help would be appreciated..