Exhaust Cam Issues

[MineralF30]

Friend of mine's car is having exhaust/intake cam issues. We replaced both camshaft gears and the bolts, then put everything back together, and we had these codes: 3011 & 3012, which are "intake & exhaust camshaft installation faulty"

So by that point we figured we timed the motor incorrectly. We removed the valve cover again, replaced the bolts, retimed the motor properly & torqued to bolts to spec, but this time the intake code went away but the exhaust code is still there.

Can anyone chime in and help us out? We've been stuck doing this for over a week and can't figure anything else out.

Car is a 2011 N55 6MT.