ZD30 common rail misfire

Hey guys, I've recently acquired a 2009 GU Patrol (ZD30 common rail)
its a completely new thing for me coming from a 95 Hilux!
It does run but has a misfire, chucked a scanner in this arvo and its throwing this code (P0523 / Engine oil pressure sensor circuit high voltage)
Motor is visually quite healthy looking only leak found was in the turbo oil return line.
all except one injector look clean, one has oil residue around it, was told by the previous owner that one injector was clogged which leads me to point fingers at the spunky looking one,
my next move is to buy some new injectors but i obviously am not completely sure what the go is,
wondering if anyone else has experienced problems similiar, its quite clear that i don't know exactly what i'm doing,
i have no problems taking the car to a mechanic if the problem is way out of my league but thought id ask on here first!
thank you! :)

Change the oil pressure switches first maybe. There is two of them. They are cheaper than injectors.

if the oil is around the injector need the firewall then it could jest be oil dripping off the intercooler