I do understand your concern about Molly; this is a very frustrating situation when you have a dog who doesn't like dog food...and who's smart enough to pick out the pieces of human food that they prefer!
There are several suggestions that I can offer although I readily admit that they don't work in every dog.
1. Mix very lean hamburg since the fat is not in a very high concentration to cause issues but often enough to coat the kibble.
2. You can try to "trick" her into thinking that dog food kibble or canned food meatballs are treats; you basically use them as rewards during training sessions rather than feed specific meals.
3. You could feed her a home cooked diet such as boiled chicken/hamburg/egg and white rice, along with some veggies (raw or cooked) After a couple of days or weeks, start sneaking in some dog kibbles in the mix, and slowly change the proportions of human to dog food.
4. There are sauces available these days that are formulated for dogs and are designed to make their dog food more palatable as well; most pet stores will carry them.
5. I've seen some dogs eat raw diets when they refuse the processed foods. So if you haven't tried them, this may be something to consider.
6. Some commercial dog treats are actually complete and balanced and can be fed exclusively. You'll just need to check the label of the products for an AAFCO statement to this effect. If the label only indicates that the treats are for intermittent or supplemental feeding, then they won't be balanced.
7. If you wanted to have a diet formulated for Molly composed of only human food, there are veterinary nutritionists who can do this for you ( a list of preferred foods is given to them and they come up with a balanced diet based on those ingredients) and this service is even available online. But it's fairly expensive.
8. Some vets will subscribe to the tough love approach. Feed NO human food, only dog food. She will eat when she's hungry. I realize that this is not an approach that most owners are comfortable with.
I've had a fair number of clients through the years who only feed people food because their dogs refuse to eat anything else. I always worry that these dogs will have a decreased immune system or will fail to thrive, or have weight issues. While some of them do, not all of them will.
I hope this gives you a few other options to consider if you haven't. I do agree that this can be a very hard problem to solve.Deb