[Lawrence Coppari]

Is that oil on the non-firing cylinder sparkplug or is it fuel?

Is your injector firing?
Is there compression in that cylinder?
Is the plug sparking?

You could get a spare plug, attach it to the spark plug wire. Then take jumper cables and ground the plug to the engine. Crank engine to see if there is spark at plug. Obviously, don't hold it in your hand. Leave other plug in cylinder so there is no fire hazard.

If the plug sparks and there is compression, then it probably is an injector problem.