If that 19 hour tour of duty is correct,accurate and with no crew rest then it is something that should be raised with CASA.
Both the Cabin Crew and Pilots unions should be very concerned with this..if it is true and a regular pattern..
Jetstar is basically an Australian airline even if overseas interests have a share.
They are also operating into and out of Australian airports....
We can't do much about their pay but we should be very concerned about adequate crew rest of Australian owned aircraft and aircraft operating in and out of Australia........