I was in the same boat 2 yrs ago. My previous employer was ignoring to pay my last paycheck and threaten me to revoke H1B. I called labor of department and explained the situation to an officer. I emailed my employer saying I have talked to DOL officer and about to file claim (DOL officer gave me this email idea). Boom!! got my money next day. It's big issue for company if you file the case so they usually don't want to go through that route.
Don't worry --You'll get approved soon. Good Luck !