[RustyBumper]

When you replace the head gasket did you do a valve job with new valve guides?
What do the spark plugs look like?

 

[RustyBumper]

I gather you had a shop do the comete job? Take it back to the shop. There seems to be an obvious issue there. I agree with @new-2-me-CR_V , issues with sealing that back corner.
They are not going to like having a come back, but that ain't good and will only get worse.
The mechanics can pressurize the cylinders and close the valves to each one individually to test how well the valves and rings are sealing or where they may be leaking.
I doubt they can pressurize the crank/oil system to see if it leaks in the area you are seeing oil without blowing some seals.
Bring it back and tell them the head gasket is leaking in the back corner.

 

[RustyBumper]

Thanks for the follow-up.