The 1992 game was able to use the wolfenstein name because the trademark had lapsed the the original company had gone backrupt. While the 1992 game was originally intented to include stealth gameplay, none of those gameplay features from the 1981 game really made it into the final version of the 1992 game.
Key here is that M.U.S.E. sold no rights to id software, did not bless the 1992 game in any way, and there were no personel in common between the two games. They can't really be considered as part of the same franchise