Out of the short-list of people who saw the plane really well, only one seems to have been in a position to confirm which track (north or south) it was on, and that was Ed Paik. If the plane flew approximately over him, it was on the south track. If the plane had been on a north track, it would have passed a couple of blocks to the north of Ed and he wouldn't have seen it at all (his building faced south).
So the only witness whose opinion on this matter is worth anything, is Ed Paik, and he confirms the SoC path.