I will definitely do that. Should I do this at night when he/she is active or daytime? The other thing I've noticed is the other gecko always seems to be in the humid hide, should there be one humid hide for each of them?
I would probably wait toward the evening when your gecko is more relaxed. Wait until your gecko is active and walking around. Waking your gecko can stress it and makes you seem like a giant predator about to eat it.
You can have multiple humid hides if you want to. But mine don't seem to care and will gladly share one hide even though I provide two.