Place turkey wing on the rack in the Instant Pot and add water. Cook on manual high 30 minutes (if turkey wing was frozen solid) or 15 minutes (if turkey wing was thawed) with the vent closed. Use quick release.
Remove turkey wing and rack.
Stack collard leaves and roll; slice into 1-inch sections while rolled. Don't need to unroll.
Whisk the bouillon, garlic, black pepper, red pepper flakes and vinegar into the water.
Add onions and turkey wing.
Top with collards pressing down to fit.
Cook on manual/high with the vent sealed for 30 minutes. Use quick release.
Remove bones from wing and chop meat, adding back to the greens.