If Rhasputin's monitor is happy, then there's nothing to worry about. Not all reptiles are the same. I have a BP that enjoys climbing trees and is rarely in a hide. Does this mean that she is neglected and unhappy? No, it just means that she is a bit different, and should have these needs met. She is happy, almost always eats, and has no problems being handled. I guess she's just an odd BP. Maybe the same is true for Rhasputin's monitor. Personally, I believe that reptiles should have the 'normal' accommodations, no matter how quirky the specific herp is. If they choose to use it, then the option is there. If they don't, no harm done. Not all reptiles are the same, and if Rhasputin's monitor isn't like other Savannas, then so be it. I would recommend giving the monitor the ability to burrow if she so chooses, even if she usually doesn't dig. It may be a bit more work, but it will give the monitor the ability to dig if she wants to. I'd try changing the substrate a few times to see if she chooses to dig in another type. I would also recommend a larger tank, if only to allow for a deeper soil. You can build a new custom enclosure in a few days, and it might make your monitor happier. Seems like it's worth a try!
Also, it seems as if this thread has turned into a big attack thread. People are accusing each others' husbandry right and left, while still not having given an answer to the OP.
-Apple2