I would think the compression is low, but if they all at 150 psi, at least they are even.
Minimum spec is 140 psi. Perhaps you have an injector stuck open, (have seen this on many Holden products)
Some will stick partially open and be rich only, some will stick open and flood the engine, and even hydraulic lock the engine bending connecting rods.
Does the engine start normally, or have long crank time, and does it misfire straight after start up?
The early VZ were bad for not logging codes for misfire. VE are much better, different PCM.
A scan tool looking at O2 sensor data, before and after cats, MAF, MAP, ECT, IAT etc may reveal something.
20L/100 would be considered double average for VZ.