Honestly... I find the book weird so far. It has already claimed that Christ was born on the 25th of November and the Annunciation on the 25th of February, both a month earlier than the Church celebrated. Furthermore, there's a weird statement that Christ was born 8 years prior to what we count from and that the first four years of Christ's life were completely forgotten. What does that even mean?
What puzzles me is that her life was full of miracles and she had the stigmata and all, her visions didn't contradict anything in Scripture even though she never read it and yet I don't get it how the Church could get all of these things so wrong. I realize why the Church both didn't condemn and didn't canonize her but I somehow expect the books would be put on the Index if they were harmful but they must've gotten an imprimatur instead.
Yes, I have little doubt about her personal holiness, but she was bed-ridden and could not write. These books were produced by Clemens Brentano and not Katherine herself. So, at the end of the day, who knows what percentage of it accurately reflects things the Katherine Emmerich saw and how much is Brentano's imagination and/or embellishment? Was he interrogating her and possibly asking leading questions? We'll probably never know in this life. And, then, in between, one could be exceedingly holy and still be simply "mistaken" about having "seen" something that perhaps was the product of her own imagination. Women especially are prone to more active or vivid imaginations. St. Theresa of Avila, whenever some nun was reported to her as having visions, replied that the "visionary" should be given more meat in her diet. So Emmerich's personal holiness did not make her immune from such mistakes, nor would such mistakes be incompatible with her personal sanctity. And yet the Church has opted not to canonize her, and I would bet a lot that this has been primarily because the Church did not want to be seen as endorsing her books as if they were all authentic revelation, and thereby subject the Church to ridicule and mockery from her detractors as a result if some problems were later discovered with them.
Mary of Agreda's works were initially condemned by (the majority decision of a) large panel of theologians.