Could she possibly be dehydrated. I have noticed very similar lines between chameleons and birds of prey, and when a bird of prey is stressed or too hot, they gape their mouths and pant, which leads to dehydration if i am not mistaken.
I am far from a vet and don't really feel comfortable saying much more then that. I really have no idea what it is, that is only what comes to mind.
EDIT:
Just noticed this is your first post. Welcome to the Forums! Im Dan, Pleasure to have a new member on board, unfortunately it sounds like less then ideal circumstances that has brought you to this wonderful place. This is a great resource and the people here are amazing! Could you fill out some information for us incase its an environmental problem.
Chameleon Info:
Your Chameleon - The species, sex, and age of your chameleon. How long has it been in your care?
Handling - How often do you handle your chameleon?
Feeding - What are you feeding your cham? What amount? What is the schedule? How are you gut-loading your feeders?
Supplements - What brand and type of calcium and vitamin products are you dusting your feeders with and what is the schedule?
Watering - What kind of watering technique do you use? How often and how long to you mist? Do you see your chameleon drinking?
Fecal Description - Briefly note colors and consistency from recent droppings. Has this chameleon ever been tested for parasites?
History - Any previous information about your cham that might be useful to others when trying to help you.
Cage Info:
Cage Type - Describe your cage (Glass, Screen, Combo?) What are the dimensions?
Lighting - What brand, model, and types of lighting are you using? What is your daily lighting schedule?
Temperature - What temp range have you created (cage floor to basking spot)? Lowest overnight temp? How do you measure these temps?
Humidity - What are your humidity levels? How are you creating and maintaining these levels? What do you use to measure humidity?
Plants - Are you using live plants? If so, what kind?
Placement - Where is your cage located? Is it near any fans, air vents, or high traffic areas? At what height is the top of the cage relative to your room floor?
Location - Where are you geographically located?
Hopefully someone on here can point you in the right direction. I really only have experience with Veiled Chameleons, not sure about the ambaja/ambilobe cross you have however.