Car died and now won't start with oil pressure light on.

Quite frankly you are lost within your assessment of the possibilities.. The oil light will always be illuminated anything key is on and the engine is off - that is perfectly normal. There are multiple possible failures that will cause this crank / no start condition and the only way to discover the actual failure is via *hands-on* testing by qualified personnel.. We can’t diagnose the problem here online, sorry.