Heres a reoccuring problem. This oak leaf thread is going the way of many varanid threads, its going past the relm of applied usage. That is, I do not think an indo oak, is the same kind of OAK as our oaks. It merely has the same common name. This is true for australia, they have desert oaks, heck you can find V.gilleni and V.tristis, living in desert oaks. But those oaks are not in any way the same family as our oaks. Even if they were the same name, they have different leaves.
Now how this is similar to our horrible varanid discussions, IT simply doesn't matter, what kind of leaf for the monitor.
Leaflitter is the litter that builds up on the forest floor. This build up, is deeper and more consistant in certain areas, and particularly certain areas as they relate to the sun. That is what is important, not if its Oak or not. Using Oak leaves is not important to monitors, as the only difference is how often you have to add more to keep the a consistant depth. In nature, its very simple, if the tree, whatever kind it is, sheds enough material to maintain a certain depth, then it does. IT doesn't matter how. Only that it does.
Of interest, Neal lives near Pecan groves, pecans shed their leaves in the winter. He could acquire a huge supply of pecan leaves. But they are thinner and do not last long. But on the otherhand, he lives where its not a problem to get more. This is what is important, what is better is not a specific leaf, but access to maintain a supply of leaves. Sirs depth is important, not oak.
To make this about monitors, this is where the academic fellas fall flat. They get too concerned over concentrating on if its a oak or not. The books say it is, etc. But they forget the function. Which is simply a varanid nest using leaves as a prefered material. In all reality, these banks of leaves are usually many types of leaves. We are only picking oak leaves because they are handy for US. Oaks have nothing to do with monitors, in this case. Cheers