Turn on a multi-functional pressure cooker (such as Instant Pot®), select Saute function, and add 1 tablespoon olive oil. Add tomatillos, jalapenos, and crushed garlic to the hot oil. Saute, flipping once or twice, until lightly browned, 6 to 7 minutes. (Remove garlic earlier if it browns sooner.)

Transfer vegetables to the bowl of a food processor and puree with 2 cups chicken broth until smooth.

Clean and dry the inner pot of the Instant Pot®. Select Saute function and heat remaining olive oil. Add pork, onion, bell pepper, oregano, cumin, salt, and pepper. Stir and saute, adding more oil if necessary, until pork is browned on all sides and vegetables are soft, 7 to 8 minutes. Cancel Saute function. Pour in remaining chicken broth and scrape the bottom of the pot with a wooden spoon to loosen any browned bits. Stir in reserved tomatillo puree.

Close and lock the lid. Select high pressure according to manufacturer's instructions; set timer for 25 minutes. Allow 10 to 15 minutes for pressure to build.

Release pressure using the natural-release method according to manufacturer's instructions, about 10 minutes. Unlock and remove the lid. Stir in chopped cilantro.