I'm not sure about wiener dogs, but I would agree with most working dogs (GSP are prime example) have a high motor.
Spot on with the interdigital scent gland. Mine still used the blood in my opinion. There would often be multiple scent gland trails. Several deer in the area scented up the place. Blood trail along with scent trail was nice. At least when they lost blood you knew it was the same deer the dog was following (most of the time.). I still say (almost) any dog will work. A big part of tracking is the handler being able to read their dog and what the dog is telling them.