They do need other vitamins and goodies than just the calcium and d3. do you gutload the crickets well? I'm thinking if she's nice colors and eating and drinking fine that its not stress. I dont understand why she would get uri in a screen cage and no stress. loosing her grip could easily be due to not gutloading if you dont do that... also does she have any live plants? they love to eat ficus and pothos and hybiscus, that gives them nutrients that crickets dont...
Have you checked the temp at her basking spot? mine will climb on the screen and bask for hours with mouth wide open till I move the heat lamp, never drooling though...
I dont think the humidifier would cause uri unless it had some sort of bacteria growing in it... normaly 35% is real low for chams, you should try to get it around 50% at least, normaly when a cham is sick you should try raising the humidity and temp a few degrees. As long as she's eating and drinking good...I really dont think its uri...they usually stop eating and drinking with uri and that becomes the critical point where they dont turn back. I dont think I would worry about that as much as loosing the grip and falling.
I know she would probably be more comfortable in her cage, maybe you can place a thick towel folded many times on the bottom of the cage for padding...I did that with a cham that had no toenails and kept falling. do you clean the cage good? no mold or anything in it? just trying to think of possibilities...
what color/texture is the poo? is the urates (white part) acctually white?
I think that if eveything looks good no mold, proper gutloading or vitamin dust, poo looks good, cage not moldy or anything, and she does not get better that you should look for a good herp vet...maybe they can take a fecal and/or blood to see if everything is working good inside.
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From Sunny Florida
Jovana's kids listed below
1.0 Veileds
1.1 Ambanja Panther
1.1 Tamatave Panther