If you really feel that a dangerous situation occurred you should report it. Start by contacting ATC at the airport and discussing the matter. If a large aeroplane really was that far below the glidepath it is very serious. I'm sure that had that happened, ATC would have instructed the aircraft to climb and they would have filed a report.
I'm still surprised that it didn't make the national papers... and there's nothing on here in the flight deck forums..