Re: fuel in the oil
A non-Marine mechanical fuel pump can pump gasoline into the crankcase if the diaphragm is compromised.
Some carbs have plugs in their bases that can start leaking fuel right from the fuel bowl into the intake manifold.
Some carbs have a rubber diaphragmed power valve that if ruptured will leak right from the fuel bowl into the intake manifold.
In either of the last two scenarios the entire fuel bowl can drain this way, any residual pressure from the fuel pump can let even more fuel get into the carb as it drains. The fuel can work it's way past the rings into the crankcase.
If it is one of the last two scenarios then while trying to run the engine the engine will flood and run very poorly if at all at idle, will be hard to start and will foul the spark plugs.