He'll be fine...you're not killing him!

High humidity for a few days won't hurt him. If I were you, I'd just let him settle in for a week. Don't feed him tomorrow, just wait a week and leave him completely alone. Then try to feed him. If he eats...give him another couple days...(for digestion)...then transfer him to a temporary holding tub so you can solder a few more holes in his home.

A couple other tips to lower humidity without being intrusive...make sure the water bowl is on the cooler side of the tub...and maybe try a smaller water dish with less surface area for evaporation.

Good luck with the little fella!!