2020 Ttanium Hybrid/2009 Limited Hybrid/1978 F-250 Custom
I was guessing you wouldn't get compression in the cylinder with the oil in it, but I am surprised you have got zero compression in all four cylinders…My son actively cranked the engine with the key in start, clutch pressed, and wide-open throttle. The needle didn't budge.
That leads me to think Dwight is in the right Neighborhood with the topend - valves/camshafts/timing chain
It's weird it happened overnight.
Did you hear it running the night before? I am just wondering if it had developed a misfire or a knock before it was turned off. Maybe ask your daughter if it dieseled on after the ignition was cut... anything acted or sounded different.
Sometimes you have to ask the right question… It was running, but how well? ( : with an oil soaked spark plug, it had to have a healthy misfire
I wonder if it could be something 'simple' like a cam/crank position sensor(s) for your no start issue? I don't know if you can electrically test one. I think you got two camshaft sensors because of the DOHC. They are at least not expensive. I think you have to remove the timing cover to get to one though
Maybe you were lucky, in that it made you find the oil in the cylinder… before the engine blew up.
try to look for the silver lining! ( :