Those are the two likely culprits.
The timing chain one used to weep on my 53 plate car.

 

I cant post pics yet as i dont have permission, need to sort my membership out.

I have taken a pic this morning and again oil is present and it appears to be weeping through head in the middle of the casting ,again not visable flaws in head. I am positive (and honda are too) that it is not coming from any surrounding seals.

 

Send me it and I will post it.