This is why it's never a good idea to smash hardware. It never results in any benefit to the hardware or the user.
That said, there's always a way to fix something that's broken. Whether it's worth it or not? That entirely depends on your point of view, but I would wager probably not considering what the mouse costs new.
Try contacting the manufacturer and see what they would charge to fix it. You can also ask for the cost of the parts if you wanted to replace it yourself.