Bypass touch switch on humidifier circuit board
I am not sure about touch sensitive switch.
Try to solder 2 wires to the switch and connect to an external push-button.
If your device starts with this external switch, then you can add a timer on delay, one second time.
The coil will be connected to the supply voltage, and a normaly closed contact wired in parallel with the touch sensitive switch. That way you will get a pulse whenever the supply is switched on, and the device will start if everything is Ok. Safety will be as if you had pushed the touch sensitive switch by hand.