You said..."Seems he's not just "falling" off. He is grabbing his front leg with his hind leg and won't let go. He seems to think he's holding on to a branch and then when he decides to lift his other hind leg he loses his balance and down he goes"..could be MBD. A vet could tell your friend for sure and if it is give the chameleon injections of calcium to get it back in line quickly.

You said..."I DID also ask her when she changed her UVB bulb and it had been almost a year, so she has a new one in and everything else that would normally pertain to husbandry seems to be in order"...could you find out what brands and types of supplements are used and how often with each? She needs to look at what is fed to the insects too. Is the new UVB a tube/linear bulb or a compact?

Does/can the tongue shoot out fully?
Does the chameleon have any deformities to the legs/arms?