I don't think an Australian pilot was in command of this Jetstar flight, can't be because I heard that they are the best, top notch. Maybe the SIN ATC was at fault for not warning them earlier that they did not have their landing gear down. You know, the SIN tower controller should have them in sight through his binoculars.
Another reason was maybe the VHF communication on SIN tower was so bad he tried using his mobile phone to contact the tower. Don't be so quick to judge, people.