It's is exactly the phrase "Не даром же мы поэт" - not the best phrase from my point of view
The "changing" letters are probably "д" and "т" - it's fine - it's the handwritten kind of letters
I'm actually wondering how it's supposed to be "не даром" or "недаром". From the context it looks like it supposed to be "недаром". What kind of "Russian edition of the book" we are talking about here?
Why does she want Dostoevsky phrase?