Okay, so this has came to my attention. I'm not entirely convinced it's legit, it just sounds a bit too later-than-1996 to my ears, but that's not to say that Ralphi Rosario wasn't asked to make a remix of "Stupid Girl" for club play years after the single was out, or that he did on his own for his own DJ sets. I'm not sure what the source of this was either.

Ralphi Rosario is a Chicago house DJ, known for his remixes for Madonna amongst others. He also remixed "Bleed Like Me" for club play in 2005; both remixes of his were not accepted by Geffen's A&R and leaked online over the years:

🎧 Garbage "Bleed Like Me (Ralphi Rosario Hydrate vocal mix)"    • Garbage - Bleed Like Me (Ralphi Rosar...  
🎧 Garbage "Bleed Like Me (Ralphi Rosario Leather Daddy dub)"    • Garbage - Bleed Like Me (Rosario Leat...  

Fully official remixes of "Stupid Girl" commissioned for Mushroom Record's UK release of the single by Red Snapper and Dreadzone, plus remixes of "Stupid Girl" commissioned by Almo Sounds/Geffen for the USA/Canada single release by Todd Terry, Rabbit in the Moon, Jason Bentley and Danny Saber are available on the 2015 digital album 'Garbage: 20th Anniversary Super Deluxe Edition'.