HELP! Mamiya 7ii Shutter Dial "Fell" off
So I just rented a Mamiya 7ii from my school, and when I got it, the battery was installed upside down and the shutter dial was very sticky. Well, in my infinite wisdom, I kept turning the shutter dial, thinking that someone unscrewed it and I was screwing it back on. NOPE! The shutter dial fell off, and now I have no idea what to do. The equipment locker is closed, and I need to try to get this fixed so I can shoot my homework over the weekend.
So if anyone has experience with a Mamiya 7ii and knows how to fix this, let me know!