Was the original photo from the back cover with the lady attempting to escape the grave with a hand around her neck ever featured in a version of the first Evil Dead?
I'm not sure what you're asking there, but if you're asking if there's a cut of the first Evil Dead film that features a scene similar to that, the answer is no.
The original photo I can find appears to be a still from footage, is there a missing scene relating to this to ever surface?
It isn't a still from footage and once again, the answer is no.
I have also seen various version of this shot used as the full size front cover of the cassette insert.
That shot is from a photo shoot done a while after filming to gather images for use in promotional material (such as posters, VHS covers, etc). It was used as reference for the painted poster for the film. So maybe that's the other version of it that you've seen. There's a still photo and there's also a painting of it. Here's the photo:
And here's the painted poster: