Could two identical bikes require different pin positions for front derailleur cable routing?
For the most part every bike model will use the same position for the converter. 

What the converter essentially does is give some adjustability to account for different points of origin off the BB shell area for the final run of exposed cable before the BB anchor, because the derailleurs that feature converters have an anchor point whose lateral coordinate is very close to directly over the pivot of the actuation arm and are thus more sensitive to how the angle of approach of the cable affects the total throw of the cage, compared to traditional derailleurs where the anchor is more off to the side of the arm pivot.

Because these derailleurs are sensitive enough to this angle to require all the fuss of a special tool etc, it's conceivable that in some cases that small variances in layup, the exact position of a cable guide hole in the BB shell, etc, could cause enough variance for different bikes of the same model to need the converter set differently. And it would be very likely for this to be overlooked in a factory assembly setting.