Does the computer you use include in addition to Avogadro an installation of OpenBabel (project page, page to obtain an executable for either Windows, 32bit, or Windows, 64 bit)?
For an instance of Linux Debian 12/bookworm with OpenBabel and the AppImage of Avogadro 1.97 (the later downloaded on March 23 from this source), Avogadro reading your file starts with a question if the guessed format is correct
Since this indeed is good (match with the first couple of lines’ content), I proceed by “ok” to enter this display
