Meh, that's mildly dissapointing. Too sylvaneth specific to be all that nice in combined forces. Though chameleons still benefit from them with some charge protection I suppose given that the chamelons themself won't run or charge themselfs (outside of particularly weird situations)
One tactical question would also be: place the chameleons behind the wyldwood so you don't hit them when you make the trees attack, or place them on the wyldwood to get their 3+ save, but risk wounding them when the trees attack.
Meh, if you're going that way, get something that doesn't benefit as much from cover and with longer range, e.g. a cannon. Then use the Woods as a blockade to protect your artillery.