Hi Conrad - how is the rescue doing? He is certainly in fine and caring hands 
As for the humidity issue with your other cham...I live in NH where it is extremely dry from November thru April/May so it is a daily concern. I, and others, have opted for a humidifier with PVC pipe attached to guide it right into the cage. I then use some plexi-glass pieces as baffles just to keep the moisture from getting into/onto/under light fixtures. I prefer it to a fogger/mister (not that I have tried them), but from others keeper's experiences. I like this method and the control it allows. The only real concern, if it even is a concern, is that it is cool mist. What I do to balance, is to bring her cage up to a high basking temp of 95+, then turn it on. Luna will literally climb onto a specific branch to be in the mist - damn I just love her 
I use the Sunbeam which can be found here: http://www.sunbeamhealth.com/productdetail.asp?id=52 and I spent about $5 at home depot getting the pvc I needed. Here is a pic of the setup. You can go to the gallery and look under "lele" for more if you want.
hope this helps! Oh, regardless of what you use, clean it often (though I am sure you know that). I take the PVC out whenever it is not in use and then clean the tank daily - but I tend to be obsessive ;-/
lele


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0.1 veiled - Luna
0.2 felines - Kyndra and Líta
1.0 African Clawed Frog - Skipper
0.5 Mad. Hissers
0.1 Chilean Rose Hair Tarantula (no name yet)
?.? Goliath Bird-Eater Tarantula (no name yet)