That is an awesome idea!
Yep, cell charger current is too low.
I doubt the Airwick has any voltage regulation built-in. But 3.3V is a common max voltage for microcontrollers, so it can probably handle that voltage without a problem; and that opens up a few possibilities. Plus you'd get more motor torque too.
Yes it can handle 6V, the cellular charger i tried is 5.6V / 380mA . But, like i said motor wont work, it makes some faint buzz but it wont move