Probably not. The megapuls only switches on just before 12V. Since you can no longer charge it, this will not work. If you can raise the voltage to about 12 V, it might work.

It worked for me with an even more deeply discharged battery. It was usable again after a longer pulse cure - but no longer in "new condition". It could no longer retain much charge. But it was still good enough for "normal" use in the vehicle.