That doesn't sound like a hg to me. Any smoke while driving? Usually coolant will be burnt if a bad head gasket. I may be wrong but I don't think the oil is pressurized running down those channels while the coolant would be. I think the gasket would be totally gone and head warped for oil to be seeping in.

From the vc gasket the oil wouldn't necessarily cover the whole plug. Just depends on how much it's leaking. I would run for a bit and pull them out again. If the plug is wet soaked on the electrode that cylinder wouldn't fire. I bet it's picking up the oil when you remove the plug. Ccv as others have said is Likely too.