This is no longer true. QFi uses 3xx flight numbers on QantasLink operated flights.
The Palau route uses QF165/166, Norfolk Island uses QF183, QF184, QF179, QF180 and they are all gov contract flights (operated by a 737) meanwhile QF357/QF358 to/from HIR, QF359/360 to/from NOU, QF355/QF356...