Zarlak
my face causes global warming
Your theory falls down in one particular points.
If the referee has seen the handball then he is obliged to issue a yellow card to Nani for deliberate handball.
If, as you suggest he was playing the advantage, the next time the ball goes dead he must issue Nani with a yellow card. The fact he's allowed an advantage does not stop him from his obligation to issue Nani with a yellow card.
Did Nani get a yellow card for the handball ? No he didnt. Therefore its 100% guaranteed that the ref didnt see it.
( and the fact the cameras caught him admitting as much to Gomez does suggest he didnt either )
Not at all fred, how many times do we see divers not getting a card even though they should do? Hundreds. Just because he wasn't carded doesn't mean he didn't see it. Happens all the time where divers are caught out and not carded.
Therefore the theory stands fine, it isn't 100% guaranteed that the ref didn't see it just because Nani wasn't carded.