Well, I might as well chime in like the non-expert that I am.
I've got a hunch that it's stressed to the max. Have you been handling it and/or do you keep peering into it's cage to check on it? If so, stop, leave it alone, give it complete solitude.
After force-feeding it you'll be lucky if it comes out of hiding within a week. That's seriously scary stuff to a young monitor in new surroundings.
Give it a box just big enough for it to fit inside, with an opening just big enough for it to enter. Cover the outside of your tank/cage with paper or something so it can't see out and you can't see in. Place the tank in a quiet part of the house and forget that it's even there for about a week. You can offer it fresh-killed or frozen/thawed rodents after about 5 days or so but don't go disturbing it's hide box or uncovering the monitor if it's buried in the substrate. Toss rodent in quietly & quickly and leave it alone. If your caging conditions are good it will liven up in time.
Hang in there!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American

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