What are your humidity levels without the fogger?. You probably don't even need it if you run a dripper and mist periodically. Foggers can create too damp of conditions which can lead to respiratory infections. I would run the dripper all day long and have some sort of shallow container to catch the water below or you can use something deeper if you cover it with screen or something some your chameleon cannot fall in and drown. The misiting can be done like 3 or 4 times a day for intervals of about 3-5 minutes. If you don't mist long enough, some chameleons will not drink.