How do Ocean's 13 rip Bank of 500 million dollars in one night?

In the movie Ocean's 13, they rig every game in the casino in order for Bank to lose as much as possible. But once everyone is on a winning streak, Danny gives the green light to start the "earthquake", forcing Bank to go to the room where the Greco is stored and forcing it to reboot due to the magnetron in his cell phone. But in the 3 minute window when the system is dowm, everyone wins big but no one ever cashes out! Only when the earthquake intensifies do we see all of them running to the exit with chips, not cash. Rusty does call out to everyone around him to cash in but there's a stampede of people getting out, and not waiting to cash in. Since most of them didn't cash-in, Bank could easily change the chips the next day, causing the existing chips to be worthless, just like the movie 21. So my question is; did Bank really lose 500 million that night?