i'm not a minoxidil expert at all, but from what i read here and there you could develop hairs, if not on your finger, on various areas like ears, above your eyebrow and so on.. because it can penetrate on your bloodstream and so spread over zones that aren't beard related
Since you only lack of connectors, if i were you, i wouldn't use chemical substances at all, unless you are ready to transmutate into a werewolf