I've totally stopped misting the past year and my frogs are happy as can be. I make sure the substrate is nice and moist, add water as needed. remember if your frog burrows the substrate will still be wet under even if its bone dry on the very top.

When it gets this dry on top, I will pour some water on and mix it. Seeing as I take them out AT LEAST once a week to feed them, and re-moisten the substrate every time, I barely find myself having to add more water between feedings.

If you want to mist, you have to invest in a good gauge, a lot of them don't work. Keep in mind, if you are misting, it is not possible to keep a constant humidity any more than with my method of keeping the substrate moist because humidity is measured in the ambient air, if there isn't a constant source/proper conditions for keeping that humidity in, then it won't remain steady.
Unless you are measuring your humidity by having your monitor in or right above your substrate, then it is still only measuring the immediate humidity which is rather pointless to mist as opposed to wetting the substrate once a week .

Also, have a BIG water bowl. When I had a water bowl, my frogs would stay in it max 1 day, now that i made my tank 50/50, my male frog stays in the water side ALL week between feedings, and hasn't left it for the past 3 weeks. Absolutely LOVES it, my female spend 4 days in the water.
This will eliminate the possibility of dehydration/drying out also.

I couldn't recommend anything more than having 50/50 split, to allow the frog to swim freely