It's normal for a lot of scorpions to turn into pet holes from time to time, especially if gravid.
Is your piece of bark vertical? Bark scorpions tend to climb if given the opportunity, so if you put something vertical in you might see her more often.
Also, I wouldn't assume it is pregnant just because the dealer said so.
If your emperor scorpion stops eating, don't panic.
Be nice -- you were a noob once, too
"Never ask an engineer to explain something, because he will."