The loss of oil pressure could have been a loss of power to engine harness or gauge. The rule of thumb is “ believe your instruments until proven wrong “.
You can hook up a temporary mechanical oil pressure gauge to prove oil pressure. If you don’t get pressure on a mechanical gauge, stop immediately and get help.
A quick test of the gauge circuit is to power up engine harness with the engine not running, gauge(s) should read zero psi. Then short the pressure sender’s two leads with a jumper lead. The gauge will either stay at zero or peg high. Then remove the jumper and one lead off the sender, it should then peg the opposite direction.
On the unexpected shutdown, does your engine have an electric fuel pump?