Damsel in distress

The oil in the photo of your engine may have come from the sending unit if it went bad.
Check to see if it 's damaged or not. As someone else said if the diaphragm went in it that could account for the noise and all the oil. The top may have come apart and made the noise when it hit something. It's hard to tell from the photo if it's all in one piece or not.

As for the wire you have in your hand in post 100, that looks like it would connect to the oil sender. It being so made me question if it's a bad oil sender.
The engine produces 45- 60 pound of pressure which would make the oil spray a bit. This is just a theory I maybe totally wrong.

It's always better to check the cheapest things to fix first instead of major things and have pay for something you don't really need to have done.
It may only be combination of small things that need to be fixed and nothing major.
So don't give in yet. Good luck on getting it figured out.

View attachment oil.jpg the sender is circled in red.