I am a PI and this seems to make sense at least in one way. If the woman really doesn't want to be with the guy but feels she has to for economic reasons, then she's obviously way more inclined to cheat on him.
If a man isn't being sexually fulfilled by a woman, he is also way more inclined to cheat. These days with the courts not in favor of men though, any man who loves his children will stay faithful no matter what neglect occurs.
Be careful with using electronic devices to spy on your own partner. At least in the USA there are federal wire tapping laws. It doesn't matter if it is your spouse. People have to be extremely careful about how they do surveillance of their spouses.
RE: Economic dependence and cheating: a study reveals a possible correlation