Legal Question in Employment Law in Maryland

More information is needed but generally yes, an employer does not need to pay for hours not worked. If an employee works 20% fewer hours they would usually get paid 20% less than before.

For a salaried employee the answer is more complicated. A true "exempt" salaried employee (e.g., management) should get the same pay irrespective of hours worked and shouldn't get pay docked because of fewer hours worked. Conversely the salaried employee isn't entitled to overtime for additional hours worked. The relationship between work hour expectations and pay for a salaried employee can become complicated and a position / pay shift might be permissible while docking an exempt salaried employee's paycheck would not be okay.

While I hope this general information helps you are encouraged to seek personalized legal advice for help analyzing your particular situation.