Can text messages be pulled from the phone of the elder or elder's exploiter to prove undue influence and financial extortion for hearing in IA?

Recently filed petition for elder abuse in IA. My father in law has been giving money to a stranger for about 9 years since the passing of his wife. He is a lonely old man living in a wonderful local senior center. This 53 year old bible thumping African American woman has brainwashed my 92 year old father in law into believing he was her answered prayer from G_d, calls him Grandpa. He likes to be needed says he can't sleep at night knowing that she can't survive without him and gives her whatever she asks for including vehicle, insurance, rent, tires, maintenance, computers, etc...all cash. She is a highly educated woman who can't seem to hold a job very long and somehow just needs his money for her scam I mean survival. I recently determined that she is married so she and her husband are living off my father in law's income depleting the estate of it's inheritance. My husband is on the verge of a nervous breakdown, it has caused him great angst. Please help!