Place chicken in the bottom of the Instant Pot. Add salsa verde, cumin, garlic powder, and cayenne. Secure lid and set on the "Poultry" setting on the Instant Pot, or for 25 minutes on pressure cooker. Do a quick release as soon as the cooking timer is finished. Lift lid and shred chicken (it is easier to remove the pieces one or two at a time and shred in a bowl or on a plate). Return shredded chicken to pot. Mash the beans from one can into a paste and add to the pot. Add remaining three cans of beans, and chicken broth. Turn Instant Pot saute setting to medium and warm the chili stirring occasionally. Once hot, add heavy cream and stir. Warm through and then stir in the shredded cheese. Serve warm, garnish with avocado pieces.