The enzymes they use for carpet cleaning, to remove organic matter, might cut wine, dabbed on to sit for a day or so (wet, under a damp washcloth), and then wiped back out. It might cause the staining, organic part of the wine to loosen up enough to be amenable to bleach.

Did you call a stone floor contractor, tho, because they would know what acid would eat it and not hurt the stone, and how to neutralize the acid after it's done its job and re-seal the stone.

~S~