This is a judgment issue more than a skill issue.

GPS NOTAM'd as unreliable on a dark, moonless night?

Fly the ILS approach (or fly a visual approach along the track of the ILS approach backing up your visual with the radio signals). That will give you terrain and obstacle clearance all along the route using locally generated navigation signals that will be entirely unaffected by GPS jamming.

https://aeronav.faa.gov/d-tpp/2607/06922IL24.PDF

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plorg an hour ago | parent [-]

Per other comments the ILS approach was not available due to the local weather service being NOTAM'd as unavailable, couldn't set local altitude. The judgment call was effectively whether to take the flight at all, as there was effectively no instrument approach available and the visual conditions precluded VFR.

	▲	sokoloff an hour ago \| parent [-]
		The ILS approach being not legally usable as an approach due to a missing local altimeter setting does not make it unusable to back up a visual approach [or VFR arrival]. I would 100% (and have) take center's altimeter setting and fly the track of an ILS or localizer rather than "whelp, nothing can be done..." This was VMC; you don't need a local altimeter setting to be safe using the radio navaids; you would need it to legally fly the approach as an ILS approach.