Here in 2 Nephi 4:17, Joseph Smith deleted notwithstanding, probably because he didn’t like the potential double negation of “nevertheless notwithstanding”. Nonetheless, this editing created a disconnected sentence fragment (“nevertheless the great goodness of the Lord in shewing me his great and marvelous works”). Thus the 1920 LDS edition restored the notwithstanding, undoubtedly by reference to the 1830 edition. Clearly, the notwithstanding is needed.
Elsewhere in the text, there are other examples where the two negative connectors nevertheless and notwithstanding occur within the same clause:
These two examples suggest the possibility that “nevertheless notwithstanding” in 2 Nephi 4:17 might have originally had an and between the two negative connectors. Nonetheless, even without the and, the earliest text in 2 Nephi 4:17 seems reasonable enough, and there are only two examples with the and, not enough to support further emendation.
Summary: Maintain in 2 Nephi 4:17 the combined “nevertheless notwithstanding”; Joseph Smith’s deletion of the notwithstanding led to a sentence fragment, which was corrected in the 1920 LDS edition by restoring the notwithstanding.