Set an Instant Pot or other multi-cooker to sauté on the highest setting. Meanwhile, chop the bell pepper, slice the garlic and halve the chile pepper. When the pot is hot, add the vegetable oil, then add the bell pepper and garlic; cook, stirring, until softened, about 3 minutes. Turn off the sauté setting and stir in the rice, 1/2 teaspoon each jerk seasoning and salt and 1/2 chile pepper. Stir in 1 1/4 cups water until well combined.
Set the rack insert over the rice. Season the chicken all over with salt and the remaining 1 1/2 teaspoons jerk seasoning; place on the rack. Put on the lid, making sure the steam valve is in the sealing position and set the cooker to high pressure for 1 minute.
Meanwhile, drain and rinse the pigeon peas. Roughly chop the cilantro and slice the scallion. Grate the zest of 1/2 lime, then cut the lime into wedges. Finely chop the remaining 1/2 chile pepper.
When the time is up on the Instant Pot, let it sit for 5 minutes, then carefully turn the steam valve to the venting position to release the pressure. Remove the chicken and the rack. Stir the peas, scallion and lime zest into the rice with a fork. Discard the chile half and stir in the chopped chile and cilantro.
Divide the rice and chicken among plates; top with more cilantro. Serve with the lime wedges.