how do you know no one edited what prophet mohammad had recited? were you present there to note that the scribes only wrote what he had said and no one edited it? whts your evidence that no one made gramattical corrections? i certainly think someone could have done it. you’re taking your religious books word for it. this is not evidence, its your belief.
have you heard what critics of islam say about Quran, and the prophet? ofcourse you will refute that as it goes against your belief. I am not going to mention those claims here as people tend to get offended very easily if a word is said against islam. but you can easily find alot of criticism on different websites which go into detail on contradictions, abrogation, error in compilation, and tons of other controversy which clearly show how it cannot be the true word of god. I am not saying whether all these accusation are true or not, but they are there for those who wish to see the other side. you can believe whatever you want, but there is always critics of every faith. so for you to think that your religious book is free of any criticism, is completely false. so when you come up with criticism against the book of Mormon, just remember, there is also criticism against your book.