Personally I see a couple of things wrong with the room idea.
#1 if the room was set up properly you would never find your animal.
#2 It could be done and it would really be a beautiful set up but it is gonna cost some serious $.
#3 If you are giving an animal a "wild" set up you need to be ready to accept "wild" behavior and health issues that may or may not come with the territory.
Here are just 2 examples off the top of my head.

*I wild balls do not eat a small rat once a week nor do they eat frozen
thawed. you would have to find a new way to introduce food to your
animal and be prepared for them to eat at a more natural frequency.
*You would need a thick layer of dirt as substrate to have burrows dug
in and for the "savannah" grasses to grow in. (which by the way
should be heated to radiate heat to your animal) How would you
clean that? Bacteria would build up that may make your animal sick.

Don't get me wrong I love "wild" or naturalistic enclosures they just need to be very well planned and thought out with the animals needs in mind and then the person implementing them needs to have sufficient $ and man power for their building and upkeep.