Misuse of Funds

I found out that my son's mother was collecting survivor's benefits on his stepfather when he came back to leave with me last year. She's been collecting this since 2001 although he lived with me for 5 years of that time. The payee was changed when I discovered the benefit, but she later started harrassing us saying she was going to get a lawyer to get reimbursed for the funds that were sent while he was living with me and I was supporting him. My wife called the local security office and was told to disregard her threats. She also gave the information about the five years that he lived with us previously. The agent verified that the checks continued to go to his mother who lives in a different state. My wife asked if the phone conversation counted as an official report of misuse of funds by my ex-wife and was told yes, although the agent stated that she didn't need the documentation that was offered (school records). Will this be investigated?