Is my marriage valid if my wife had been misled by an Amil and had Sehar-related kufri things in her possession?

I am married to a sunni Muslim girl since 2 years and after marriage I discovered that in her house she had bandish in the corners of wall across the house. I later removed all those and found that it was not a Quranic verse but Sehar related things. I questioned her and she said that She doesn’t know what was inside it and she might have been misguided by a Maulana who apparently was an Amil. She said he cheated her of money and he had such an influence on her that he would charge her money every now and then and that she no longer is interacting with him. I explained her about tauheed and shirk related matters. I destroyed most of them and asked her to dispose off the remaining in her possession.
After 2 years I found some material or papers that had Sehar related kufri things written on them. She says she does not know or remember anything.
I want to know is the nikah valid or not with such kind of a person. She offers salah, reads Quran and observes other things.