What part of "the run wonâ€™t be world record-eligible on a sanctioned course" do you not understand?
If you are running the course on a non-records eligible course, then you are receiving assistance - either by wind, elevation drop , etc.
A course has to start and finish in the same area to be record eligible.
It can't be point to point.
So if you run 26.2 miles straight ahead and it is uphill with wind in your face and run sub two it would not be eligible for a record, even though no assistance was received.