No fake leaves in cham cages.... Especially not for a Veiled since they eat their plants so this becomes a major impaction risk.
For other species that do not eat their plants I would not use anything other then the reptile fake plants. The ones that you get in hobby stores are not made to handle the humidity and moisture we put into our cages... Leaking out their dyes into the enclosure is not something you want not to mention most other species drink from plant leaves. So they are then ingesting whatever was used on the fake plants.