It's special because it was developed as part of an existing (reasonably noteworthy) franchise but never released to the public, so the version in the Library of Congress is probably one of very few in existence.

The screenshots in this blog post contain only small excerpts of the disc's contents, transformed substantially from their original format, so they pretty clearly fall under fair use.

Even untransformed excerpts/screenshots would almost certainly be fair use in a scholarly article about them. The LoC knows a thing or two about copyright.