If he is opening his mouth there is a couple of things that could be going on. Either it is too hot or he could have a respiratory infection. Is your humidity steady at that reading? What are you measuring your temps and humidity with anyways?
The respiratory thing was just a reason as to why he could be opening his mouth. Not saying that is what it is. You need to have variations in humdiity. Highs and lows, just like it is in the wild. I don't think there is anywhere that has a constant 95% humidity. I live in Florida and it fluctuates everyday. It can be 90% one day and 70% the next. What are you housing your chameleon in that is keeping the humidity that high and what are you using to do so? i know when our humidity is around 100% it is hard to breathe sometimes. The air is stagnant.
With gracefuls I would also agree around 50% humidity. It should fluxulate though. Gracefuls arent rainforest chameleons so I wouldnt recommend high humidity. I would think that repiratory issues would occur with such high humidity.