She can sue them in Small Claims court. Before suing, send the company a demand letter for amount they owe to their corporate agent for service of process, which you can look up on the Secretary of State's website. Send it by certified mail, return receipt requested, or by FedEx or by registered email (www.rPost.com). That way they know she's serious and she'll be able to prove receipt. Include a warning that once suit is filed, the lawsuit becomes a matter of public record, which means it will hurt their credit rating, and specify a firm deadline, 2 or 3 days from receipt of your letter, to comply or she'll have to sue in Small Claims court. If they don't comply by the deadline, follow through and sue.
Another possibility is checking with your state's Department of Labor - it may be possible to file a claims for unpaid wages, like it is in CA.
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