I don't have a specific recommendation, but pages 84-95 of the Frederick Senior Services Division has a listing of several private duty care agencies. I think you'll find that people have wildly different expectations when it comes to outsiders caring for their loved ones, hence the reviews being all over the place. Health care providers will refer you to social workers who will hand you a fistful of brochures, but not make any recommendations. Without a word of mouth rec from a trusted source, it's kind of a crapshoot.
https://frederickcountymd.gov/4651/Resource-Directory-Blue-Book