i have same thing. No McCullum in graveyard to get the king Arthur's blood
and can also see other creatures are there which can be killed
but no sign of McCullum
i have obtained both other parts already
william marshall's blood from lord redgrave
insulin in old morgue of pembroke hospital
but can not get king Arthur's blood to carry on the quest
how am i suppose to finish chapter 6 to be able to carry on with the game ?