It's safe to use, but in all honesty it isn't the most effective plant for free ranging. The foliage is situated in such a way that the chameleon can't really use it efficiently and the trunk is so vertical that that cham wouldn't sit there for comfort.
As said above, the lack of vertical branches, sharp leaf edges on flexible foliage, make this an unsuitable plant. It's not poisonous, but it could cause lacerations or falls, and if the chameleons only option, those are more likely. Included in a densley planted enclosure or free range, amongst more horizontal oriented plants, it is a more appealing prospect.
Thanks! I was planning on buying something else eventually for him to free range on but thought this may work. You are all right though I'll just get him something more suitable . Any suggestions?
Ficus allii, cinnamon tree, miracle fruit trees, Myers lemon trees (remove the rare thorns), dwarf avacado trees or other tropical fruiting trees, hibiscus bushes.....check eBay or google, as these are easily ordered at multiple stages and sizes.