The lateral guidance is based entirely on the airplane dead center, and is entirely unaffected by the POV.
What you might want to check, instead, if the accuracy of the AFCAD of the scenery you use, which far too many times we found to be lacking on a lot of 3rd party sceneries, which usually come with paths in the AFCAD not properly aligned with he actual scenery. You can fix this, by customizing BOTH the "Parking" and the "Parking System" headings with GSX, so the parking system will ignore the AFCAD, and it will only trust the headings set there.