The Grimm brothers went around interviewing busy people about stories. Not the storytellers for the most part; just regular people. They had imperfect memories of the old stories, got them confused and mixed up, and probably the whole household was competing to tell the scholars their version. Result: fragmentary and confused.
Not one of the stories in this old book resembled anything in any modern telling. E.g. There were several versions of Cinderella-like stories all different, with entirely different endings, some with no ending. Different slippers or no slippers. One or two or three sisters. Various parents dying, sometimes both! Her inheritance stolen and she exacted revenge to get it back. And so on.
The second half was more like story fragments, nothing complete. Just notes really.
So never mind 'original' versions, there may be no such thing.