Set the Instant Pot to sauté mode and add the cooking fat.
Once the fat has melted and is hot, add the marinated venison steak to the pot and allow it to sauté for 1 minute on each side. (May need to do this step in batches all the pieces of meat get browned.)
End sauté mode and remove the steak from the Instant Pot.
Pour the broth in to the pot. (Deglazing)
Stir in the worcestershire sauce and add the meat back to the Instant Pot.
Layer the onions, peppers, and mushrooms in this order on top of the steak and do not stir or mix together these ingredients.
Place the lid on pot, turn to locked position, and set vent to sealed position.
Manually switch pot to "pressure cook" for 15 minutes.
When cooking time is complete, allow the pot to naturally release pressure for 15 minutes.
Once the 15 minutes are up, quick release the rest of the steam by turning the vent to venting position and allow steam to vent until the floating valve drops.
Turn lid to unlock it, and remove it from the pot.
Use a slotted spoon to remove the steak and vegetables from the pot.
Separate the steak from the vegetables and using 2 forks, shred the steak into bite size pieces.