If I give an instruction to an ac to turn left onto North now (even if he is finals at 300ft), I expect him to configure the ac before commencing the maneouvre (ANC), that is taken into account when I give the instuction...
Perhaps he tried to. About 30 seconds passed between the original go-around instruction and the turn to the north, which seems to have been made after the controller's confirmation of the instruction.
He was instucted to go-around, but gave the wrong response "maintain centreline", hence the ammended instruction.
I don't think you can draw any such conclusion. The amended instruction was issued in an attempt to resolve the conflict, not because the readback was incomplete (which it was, but that's hardly surprising since the original phraseology was highly non-standard).