Infiniti: 95 J30 parking brake adjustment problem

This 1995 Infinity J30 with 93000 miles failed for state inspection-
car will move in drive while parking brake applied. I tighten the
10mm nut located just above the pedal, now parking brake pedal
became more firm, I can't push the car in neutral while emergency
brake is on, but when car is running in drive, it can still
overpower parking brake.

I have not done brake job at the rear wheel, pads or rotor not
changed, owned for last 20000 miles. Need your help what it
could be that parking brake wont hold the car in drive. If I
tighen any more the 10mm nut, it may break the brake cable.

Any suggestions.