Place kidney beans into a large container and cover with several inches of cool water; let soak for 2 hours.
Turn pot on "Saute" mode; add olive oil and sausage. Cook and stir until sausage is browned, about 5 minutes. Add onion mix and garlic; cook and stir until onion mix is soft, 5 to 10 minutes. Turn off pot.
Drain beans and add to pot; stir in chicken broth, Cajun seasoning, thyme, and bay leaves.
Place lid on pot, turn valve to "Sealing" and push "Bean" button, about 30 minutes. When pot beeps, use the natural pressure release until the pin goes down. Remove lid.