I saw it has chapters 55-89 missing, and the prologue of the seventh volume is before the prologue of the sixth...
LN is usually a better and more carefully written version of the story, usually used for publishing physical copies of the book, often including illustrations. WN is more of a normal online published version of the story. Author may or may not make modifications to the story from WN to LN.
The only one I know is in the WN, the MC still not graduate from the school but in LN the MC had graduate