Is it considered elder abuse when someone borrows money from an elderly person and then makes no effort to pay it back?

When I became the trustee for my mothers estate, I found out that a worker she hired had borrowed $25,000 from her when she was 91 years old. The loan is documented with a promissory note and interest has accumulated. The borrower has not responded to phone calls from the estate attorney or the collection agency. He never made a single payment on the loan in the 5 years since he borrowed the money. I want to know if he can be charged with fraud or elder abuse and, if so, what kind of attorney I need to contact in order to pursue this.