How the heck am I supposed to get my granite floor clean?

Some friends of ours came to “borrow” our kitchen and fried steaks. You know, the kind of frying that sets off the smoke alarm one floor up and around the corner? sigh
Anywho, so the entire kitchen floor and half of the dining room was greasy as heck. I have used the Swiffer Wet Jet three times (clean pads each time), and even gone so far as to use 409 All Purpose and paper towels on my hands and knees, and it still has a residue. Not necessarily greasy feeling, but if you look at the floor from the right angle, you can see streaks and sometimes footprints.

It’s driving me NUTS. What can I use to clean those tiles properly?