It wasn't only Torquay who played an ineligible player in this match. Hereford did the same.
Hereford and Torquay play ineligible player's in same game | Premiership News | tribalfootball.com
Torquay lost 1-3.
It's unprecedented for both teams to field ineligible players in the same game.
The FA can't win.
If they order a replay it's hardly fair on Torquay's play-off rivals that Torquay should have another bash at the three points.
If they dock Hereford the points they gained, but not Torquay, it punishes Hereford more harshly than Torquay for the same offence.
If they dock both clubs points it would go against precedent (clubs are usually only docked the points they won as a result of playing an ineligible player).
If they let the result stand it's not really fair on Hereford's relegation rivals that Hereford should keep illegitimately won points.
I'm glad I'm not on the disciplinary panel!