The same rule applies for irons as I stated for optics. If you’re aligning the sights the same and holding the same POA, the POI shift caused by the shooter change won’t be noticeable for a slug gun.
Any difference in POI should be (rightfully) attributed to the two shooters pulling the trigger differently, aligning the sights differently, or holding a different sight picture/POA. Don’t make a mountain out of a molehill, and don’t ignore the real mountains.