If I'm reading the question correctly you instead fill out the form MW507 so that your employer in Maryland can exempt you from Maryland income tax and withhold West Virginia income tax instead. My impression is the other form suggested applies to the reverse of the question; those working in West Virginia and living elsewhere.
The only caveat is that I believe the business then has to register with West Virginia which although easy enough to do, they might think is too much hassle if they don't regularly have employees from outside their business location. They would then file quarterly filings/payments with both Maryland and West Virginia.
