You're right. The Confessor's not looking him in the *eyes*...
It's the dismissive and completely unexpected "Yes, well, never mind old boy. You tried your best and that's all I can ask" approach which makes this perfect. The fact he's just sanctioned torture is nothing to Blood, the fact the hero exerted all his remarkable force of will to resist that torture is irrelevant, he goes out of his way to reassure the torturer that it's not his fault. Good minion management there, good torturers are probably hard to find.