As others have said, the location of the grey pin on Tesla's map has nothing to do with the exact location in the area where the supercharger will actually go. It just means that they're planning one somewhere in Parlin or in the general area. Tesla isn't even too particular about the pins going on the same jurisdiction, the superchargers sometimes end up 5 or 10 miles away in a different city/town/etc.
As for supercharge.info's map, it doesn't just duplicate what Tesla's shows. A Tesla pin isn't sufficient to get on SC.info and there are hundreds of grey pins on Tesla's map that don't yet correspond to anything on the SC.info map. To get a blue dot there someone needs to find independent confirmation/evidence of the site being in development and the exact location the supercharger will go. This confirmation/evidence is usually in the form of local planning commission meeting mentions, planning/zoning applications, building permits, etc. So, if you find anything like that, be