Yes, you certainly can use frozen chicken together with uncooked rice in the Instant Pot. If you are following this recipe and would like to replace the bone-in meat with frozen chicken, I recommend you substitute with frozen boneless chicken breasts. With frozen boneless chicken breasts, you can entirely skip the initial part of searing the chicken. Proceed with sauteeing the aromatics and seasonings, add the raw rice and liquid and place the frozen chicken breasts on the rice. Set the Instant Pot to pressure cook for 9 minutes. After the cooking cycle is complete, allow the Instant Pot to release pressure naturally for 5 minutes and then manually release pressure.