Hello and thanks for trusting me to help you and Red Dog today. I am a veterinarian with over 25 years experience and would be happy work with you.
It can be normal after a diet change, especially if she is getting less food, for her to not pass stool for a couple of days, but after over 3 days, we have to be concerned she is possibly getting constipated.
It doesn't sound like she needs to increase her activity as she is getting plenty of exercise with 4 walks a day. You can increase her fluid intake by adding warm water or broth to her food. Increasing her fiber may help as well to get things moving. This can be accomplished by adding some canned pumpkin (about 1 - 2 teaspoons/meal) or fiber powder (like Metamucil - about 1/2 teaspoon per meal).
I would avoid the turkey fat as it can lead to pancreatitis and do not give anymore raisins as they can be toxic in some dogs. Feel free to continue the belly rubs as needed.
If you incorporate the above means and still no stool is produced within the next 24-36 hours, I would definitely have her examined by your veterinarian. Even though she is not acting distressed, if she doesn't pass stool soon, she will become constipated.
I hope this is helpful. My goal is to provide you with excellent service – if you feel you have received anything less, please reply back as I am happy to address follow-up questions. Kindly rate me when you are done. Thank you for allowing me to assist you.