To make the Tzatziki Sauce, in a small bowl or jar, combine unsweetened plain greek-style yogurt, grated cucumber, lemon juice, 1/8 tsp salt, 1/16 tsp ground black pepper, 1/4 tsp dried dill, 1/8 tsp minced garlic, 1 tsp olive oil and refrigerate until ready to eat.
To make the Chicken Bowl, to the Instant Pot®, add 1 tbsp olive oil, 1 tbsp butter, lemon juice and zest, broth, rice, oregano, 1 tsp minced garlic, 1/4 tsp salt, and 1/8 tsp black pepper. Stir to combine. In a small bowl, toss the chicken in lemon pepper, then spread evenly over rice.
Close the lid; turn the knob to Sealing.
Press Manual or Pressure Cook button and adjust time to 10 minutes.
When the timer beeps, allow 5 minutes to naturally release the pressure, then remove the lid.
Scoop the chicken and rice into a serving bowl, then top with tomato, bell pepper, feta, onion, cucumber, and olives. Serve immediately with Tzatziki Sauce.