I mean, there were some weird ass bands in the 1980s scene that later became identified with the term "grunge." U-Men, Mr. Epp and the Calculations, the Melvins, and even Tad were not exactly normal. If you're just going by what was on the radio in 1992 I can't really help you there, but it was a pretty interesting time for rock music.
Yes, Geffen were able to be on trend and pour money into signing some weird ass bands to DGC, most of which were loss leaders. Sonic Youth as a legacy band are absolutely huge, even if not exactly Nirvana numbers (and as I understand it, SY got Nirvana signed and received quite the finders fee as a result).