Somehow I knew my dad didn't write that clunker of an ending! Yay.

David Kalat at TCM is critical of the original ending and believes the film is stronger for the rewrite, but . . . I'd have to see it to be sure, but all signs point to him being wrong. Especially if the climax was conceived as supernatural from the beginning: you can't just yank that sort of thing out at the last minute and expect the picture not to suffer.