Are you running Sib as 64bit or 32bit? If you're running x64 you need to go to the x64 plugings. The 32bit won't show up.
Dorico, Notion, Sibelius, StudioOne, Cubase, Staffpad VE Pro, Synchon, VI, Kontakt Win11 x64, 64GB RAM, Focusrite Scarlett 18i20, August Forster 190