Ditto on the Humid Hide.
You shouldn't need any kind of peripheral humidifier with a ball python. The humidity doesn't need to be THAT high. I have a small humidifier for the room where I keep all my snakes, mainly just to raise the ambient humidity and keep it nice and toasty in there.
I'd also like to know more about your setup. We might be able to offer some suggestions for your current setup in order to trap humidity better. Ideally you should only need to mist once or twice a day while the snake is in shed.