Set your Instant Pot to saute mode, then add 2 tablespoons of butter to the Instant Pot once heated. Sear the chicken on both sides until browned, working in batches if necessary, then remove from the pot.
Add the sliced sausage to the Instant Pot and saute until browned on both sides, approximately 3-5 minutes. Remove the sausage from the pot.
Add the remaining butter to the pot. Once warmed through (about 1 minute), add the flour and whisk the two together to combine. Continue to stir the mixture for about 12-15 minutes, until the roux achieves a peanut butter color and nutty fragrance, then turn off the Instant Pot.
Carefully pour the chicken broth into the roux, whisking continually to ensure that there are no lumps. Then add the chicken, sausage, vegetables (except for the okra), spices, and bay leaves.
Cook the gumbo on high pressure for 15 minutes. Once the time is up, quick release the pressure.
Remove the chicken from the gumbo and shred with two forks, then return it to the pot.
Turn the Instant Pot to saute mode, and add the okra to the pot. Cook for an additional 15 minutes, until the okra is softened.
Stir in the parsley and lemon juice, then taste for seasoning and add additional salt or Cajun seasoning as desired. Serve alongside rice and enjoy!