To clarify situation regarding Quantas F in SYD (currently sitting here, and just spoke with the F&B manager).
They can provide kosher meals (from Lewis), but these need to be ordered a minimum of 3-4 days in advance, preferably a week though.
To do this, you'll need to call through to the lounge directly (or call general CS and asked to be put through to the F lounge), and then let them know.
Hope this helps!