Heres the thing, your trying way to hard. And your making the cage all about you. Not about the monitors.
Lets sit down and think a bit. Many people decorate their cages in a fashion they think the monitor comes from. I call it a post card from, in your case, indo. So you think indo is all tropical and such, so you decorate your cage that way.
The reality is often very different. What you should be concerned with is what is the mirco habitat that your particular species uses.
If you have ever been in the field with varanids, you will notice, they are NOT FROGS.
Normally all varanids seek areas that are dry and sunny even in tropical areas. They are sun lovers, they are not frogs.
In your case, with prasinus, they seek open sunny areas, they seek a decent shelter, with easy access to areas where the sun hits. The shelters also have access to the sun, so the animals can control their temps without exposing themselves to danger.
So they live in drier sunnier areas at the edge of thick foliage. They are green because they normally untilize low plants, shrubs, not trees. Tree dwellers are normally a darker color to match the bark of trees. Often tropical large lizards are green as neonates as they use the bushes and green plants, then are they become larger, they move into actual trees and are often darker. Spinytailed iggies are a good example of this.
In your case, you should be provided what the monitors needs, not what you think the tropics looks like.
All I see in your cage pics is a post card from the tropics and nothing a monitor would actually live in.
You need, A series of shelters cool side, up to under the basking lite(hot spot) Retes boards provide from under the lite, very hot, under the first layer, 25F degrees less, under the second layer, etc etc down into the substrate which is your base cool temp. That is the advantage of a retes stack. If you choose to use better looking tools, then you must know what your doing and provide them where they Need to be. So retes boards are a great beginer tool. No offense, but in your case, you do not know what your doing. So why do you choose to risk your animals because you want your cage to look pretty. Ok, done for now. Cheers and good luck