Caretaker inherits all in Oregon. Is this allowed?

My daughter's MIL lives in Oregon alone. She took in a drifter to do lawn work several years ago, and now that she is showing strong signs of dementia, he has moved into the house and becoming a full-time caretaker. She recently changed her will giving him everything she owns at death, from the paid-for house and her bank account, completely ignoring her daughter and my daughter's four children. Contacting the Protective Services for the Elderly, my daughter was told that there has to be evidence of a crime, an the Sheriff has to investigate first. In the State my daughter lives in, it is against the law for caretakers to inherit property like this.
My daughter needs to know if Oregon has laws like this and how she can contact them. Her mother-in-law will not give permission to contact her lawyer who drew up the new will, not even his name. She appears to be completely controlled by the caregiver.