I didn't kick it over and therefore don't know exactly how it felt, so I can't speak to that.
However, I do know that bad rings, etc., wouldn't fill the crankcase with fuel.
It's possible that you have more than one issue going on here and leaving the gas on is merely one of them. That would explain the raw premix that came out of the exhaust and a sticking ring that became unstuck would restore compression and explain the other.
If it was mine, I'd turn the gas off every time I parked it and see if it does the same thing again or exhibited the other symptoms minus the raw fuel in the engine.
Proceed from there with what you find.
Or, as mentioned, you can go ahead and open it up now.
Your call.
Hope it helps.
:ride: