The yellow colour of the Predalien's blood offers no doubt to me: it IS Xeno blood (remember the 80% Alien, 20% Predator' remark...?)
So, what happened was that if the Xeno blood did not affect Wolf when he pierced through one with his wristblades during the HIVE fight scene, why would it be any different after Wolf had pulled out Chet's inner tongue, with all the PQ's blood hosing down right in front of him...?
'Coherence in the mistake' , I often call it... The Strauses did all they could t make Wolf a Super-Predator, and therefore rendering the Alien meek, even their blood... Yes, it can melt humans, but not Wolf... They even bluntly have him shoot an Alien at close range and no blood got on him...
I can somewhat understand this: I mean,when you have only ONE Predator fighting MANY Aliens, if you were to realistically portray it, he would have died much sooner than he did...
After impaling Chet with his wristblades, no acid destroyed his hand nor his BARE chest (after he stripped down his gear)...
So I started wondering,
how in the hell did he get the ACID BURNS ON HIS LEFT CHEEK...? Because he is clearly impervious to Xeno blood selon AVPR...!