Oil starvation can create so many problems..I would say go with another engine, even a junkyard one, than try to diagnose and repair all the damage if there was indeed oil starvation. Crank might be bent, journals could be scored, bearings would be toasted, cylinders scored, cam lobes and journals worn/scored..just a lot of things to check and clear. Pretty much an entire lower engine overhaul.
If you are/were burning oil, then you'd want to replace most of your exhaust. Things like O2 sensors and cats don't enjoy an oil dose. The symptoms leading up to it sound like ring problems or maybe valve stem seals, though I think with no power cold or hot now the rings are gone.
I've been checking the oil every other gas-up. I do it out of habit, but I've been called paranoid for doing so.